gadolinium in mri analysis

Name: Eve Kankam

TOPIC GADOLINIUM IN MRI ANALYSIS

Abstract 1

Title: Delayed Gadolinium-Enhanced MRI of the Fibrocartilage Disc of the Temporomandibular Joint

Authors: Elisabeth Pittschieler, Pavol Szomolanyi, Martina Schmid-Schwap, Michael Weber, Monika Egerbacher, Hannes Traxler, Siegfried Trattnig

Source: Magnetic Resonance Imaging, Volume 32, Issue 10, December 2014, Pages 1223-1229

Document Type: Research Article

Subjects:

Author Supplied Keywords: dGEMRIC; Temporomandibular joint; Fibrocartilage disc; MRI at 3 T; Glycosaminoglycan in temporomandibular joint

Abstract: MRI of the right and left TMJ of six asymptomatic volunteers was performed at 3 T using a dedicated coil. 2D inversion recovery (2D-IR) sequences were performed at 4 time points covering 120 minutes and 3D gradient-echo (3D GRE) dual flip-angle sequences were performed at 14 time points covering 130 minutes after the administration of 0.2 mmol/kg of Gd-diethylenetriamine pentaacetic acid ion (Gd-DTPA)2-, i.e., 0.4 mL of Magnevist™ per kg body weight. Pair-wise tests were used to assess differences between pre-and post-contrast T1 values. 2D-IR sequences showed a statistically significant drop (p < 0.001) in T1 values after i.v. CA administration. The T1 drop of 50% was reached 60 minutes after bolus injection in the TMJ disc. The 3D GRE dual flip-angle sequences confirmed these results and show plateau of T1 after 60 minutes. T1(Gd) maps calculated from dGEMRIC data allow in vivo assessment of the fibrocartilage disc of the TMJ. The recommended measurement time for dGEMRIC in the TMJ after i.v. CA administration is from 60 to 120 minutes.

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Abstract 2

Title: Late gadolinium enhancement MRI quantification to predict left ventricular remodeling after acute myocardial infarction

Authors: L. Bière, V. Mateus, S. Grall, F. Prunier, G. Clerfond, S. Willoteaux, A. Furber

Source: IRBM Volume 35, Issue 4, September 2014, Pages 182–188

Document Type: Article

Subjects: CMR, cardiac magnetic resonance imaging; FWHM, full-width at half-maximum; HbA1c, glycosylated haemoglobin; LGE, late gadolinium enhancement; LV, left ventricle; LVEDVI, left ventricular end diastolic volume index; LVESVI, left ventricular end systolic volume index; LVEF, left ventricular ejection fraction; MVO, microvascular obstruction; PTCA, primary transcutaneous coronary angioplasty; SD, standard deviation; STEMI, ST-elevation myocardial infarction

Author Supplied Keywords: CMR; Myocardial infarction; Myocardial scar; Quantitative analysis

Abstract: Infarct size is a major surrogate marker for prognosis in the context of myocardial infarction. There is a growing interest in validating a quantitative assessment approach in order to: (1) standardize these analyses; (2) to precise the individual prognosis of our patients. Several methods are available and were tested across their capacity to predict left ventricular (LV) remodeling at three months. Late gadolinium enhancement-MRI was performed on day 5 and after a period of three months in 92 patients with STEMI. LV volumes and scar parameters were assessed visually (by using a four scale score) and quantitatively on day 5 and at three months. Dichotomous thresholds were defined first visually (VISUAL), then by 2, 5 and 6 standard deviations above remote myocardium, and by the full-width at half-maximum (FWHM) method. All infarct sizing methods showed great relation to LV remodeling at three months (ROC analysis). Univariate predictors of an LV end-systolic volume index (LVESVi) superior to 70 mL/m2 were: heart failure, creatin kinase peak and infarct size at day 5. FWHM was shown to be the best of all quantitative methods. An infarct size superior to 44 grams predicted a LVESVi > 70 mL/m2 with a sensitivity of 90% and a specificity of 92.5%. FWHM reproducibility was good (r = 0.895, P < 0.0001, Bland Altman bias of 0.8 g). In the context of STEMI, FWHM is a tough and reproducible algorithm to quantitatively assess late gadolinium hyper enhancement, greatly related to functional prognosis at three months follow-up.

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Abstract 3

Title: The effectiveness of gadolinium MRI to improve target delineation for radiotherapy in hepatocellular carcinoma

Authors: D.S. Yanga, W.S. Yoon, J.A. Lee, N.K. Lee, S. Lee, C.Y. Kim, H.J. Yim, S.H. Lee, H.H. Chung, S.H. Cha

Source: Physica Medica Volume 30, Issue 6, September 2014, Pages 676–681


Subjects:

Author Supplied Keywords: Hepatocellular carcinoma; Radiotherapy; Image registration; Gross target volume

Abstract: To achieve consistent target delineation in radiotherapy for hepatocellular carcinoma (HCC), image registration between simulation CT and diagnostic MRI was explored.

Twenty patients with advanced HCC were included. The median interval between MRI and CT was 11 days. CT was obtained with shallow free breathing and MRI at exhale phase. On each CT and MRI, the liver and the gross target volume (GTV) were drawn. A rigid image registration was taken according to point information of vascular bifurcation (Method[A]) and pixel information of volume of interest only including the periphery of the liver (Method[B]) and manually drawn liver (Method[C]). In nine cases with an indefinite GTV on CT, a virtual sphere was generated at the epicenter of the GTV. The GTV from CT (VGTV[CT]) and MRI (VGTV[MR]) and the expanded GTV from MRI (V+GTV[MR]) considering geometrical registration error were defined. The underestimation (uncovered V[CT] by V[MR]) and the overestimation (excessive V[MR] by V[CT]) were calculated. Through a paired T-test, the difference between image registration techniques was analyzed.

For method[A], the underestimation rates of VGTV[MR] and V+GTV[MR] were 16.4 ± 8.9% and 3.2 ± 3.7%, and the overestimation rates were 16.6 ± 8.7% and 28.4 ± 10.3%, respectively. For VGTV[MR] and V+GTV[MR], the underestimation rates and overestimation rates of method[A] were better than method[C]. The underestimation rates and overestimation rates of the VGTV[MR] were better in method[B] than method[C]. By image registration and additional margin, about 97% of HCC could be covered. Method[A] or method[B] could be recommended according to physician preference.

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Abstract 4

Title: Tissue gadolinium deposition in renal impaired rats exposed to different gadolinium-based MRI contrast agents

Authors: Tomohiro Sato, Katsuyoshi Ito, Tsutomu Tamada, Akihiko Kanki, Shigeru Watanabe, Hirotake Nishimura, Daigo Tanimoto, Hiroki Higashi, Akira Yamamoto

Source: Magnetic Resonance Imaging Volume 31, Issue 8, October 2013, Pages 1412–1417


Subjects:

Author Supplied Keywords: Nephrogenic systemic fibrosis (NSF); Gd-EOB-DTPA; Gd-DTPA-BMA; Gd-HP-DO3A; Gadolinium (Gd)-based contrast agents (GBCAs); Inductively coupled plasma mass spectrometry (ICP-MS)

Abstract: To quantify tissue gadolinium (Gd) deposition in renally impaired rats exposed to Gd-EOB-DTPA and other Gd-based MRI contrast agents by means of inductively coupled plasma mass spectrometry (ICP-MS), and to compare the differences in distribution among major organs as possible triggers for nephrogenic systemic fibrosis (NSF). A total of 15 renally impaired rats were injected with Gd-EOB-DTPA, Gd-DTPA-BMA and Gd-HP-DO3A. Gd contents of skin, liver, kidney, lung, heart, spleen, diaphragm and femoral muscle were measured by inductively coupled plasma mass spectrometry (ICP-MS). Histological assessment was also conducted. Tissue Gd deposition in all organs was significantly higher (P = 0.005 ~ 0.009) in the Gd-DTPA-BMA group than in the Gd-HP-DO3A and Gd-EOB-DTPA groups. In the Gd-DTPA-BMA group, Gd was predominantly deposited in kidney (1306 ± 605.7 μg/g), followed by skin, liver, lung, spleen, femoral muscle, diaphragm and heart. Comparing Gd-HP-DO3A and Gd-EOB-DTPA groups, Gd depositions in the kidney, liver and lung were significantly lower (P = 0.009 ~ 0.011) in the Gd-EOB-DTPA group than in the Gd-HP-DO3A group although no significant differences were seen for any other organs. Gd-EOB-DTPA is a stable and safe Gd-based contrast agent (GBCA) showing lower Gd deposition in major organs in renally impaired rats, compared with other GBCAs. This fact suggests that the risk of NSF onset would be low in the use of Gd-EOB-DTPA.

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Abstract 5

Title: Delayed gadolinium-enhanced MRI of cartilage of the ankle joint: Results after autologous matrix-induced chondrogenesis (AMIC)-aided reconstruction of osteochondral lesions of the talus

Authors: M. Wiewiorski, M. Miska, M. Kretzschmar, U. Studler, O. Bieri, V. Valderrabano

Source: Clinical Radiology Volume 68, Issue 10, October 2013, Pages 1031–1038


Subjects:

Author Supplied Keywords:

Abstract: To assess cartilage quality using delayed gadolinium-enhanced magnetic resonance imaging after repair of osteochondral lesions of the talus using autologous matrix-induced chondrogenesis (AMIC). A three-dimensional (3D) spoiled gradient-echo (SGE) sequence at 3 T was used to obtain quantitative T1 relaxation times before and after Gd-DTPA2 (Magnevist, 0.2 mM/kg bod weight) administration to assess 23 cases of AMIC-aided repair of osteochondral lesions of the talus. Delta relaxation rates (ΔR1) for reference cartilage (RC) and repair tissue (RT), and the relative delta relaxation rate (rΔR1) were calculated. The morphological appearance of the cartilage RT was graded on sagittal dual-echo steady-state (DESS) views according to the “magnetic resonance observation of cartilage repair tissue” (MOCART) protocol. The study was approved by the institutional review board and written consent from each patient was obtained. The AMIC cases had a mean T1 relaxation time of 1.194 s (SD 0.207 s) in RC and 1.470 s (SD 0.384 s) in RT before contrast medium administration. The contrast-enhanced T1 relaxation time decreased to 0.480 s (SD 0.114 s) in RC and 0.411 s (SD 0.096 s) in RT. There was a significant difference (p > 0.05) between the ΔR1 in RC (1.372 × 10−3/s, range 0.526–3.201 × 10−3/s, SD 0.666 × 10−3/s) and RT (1.856 × 10−3/s, range 0.93–3.336 × 10−3/s, SD 0.609 × 10−3/s). The mean rΔR1 was 1.49, SD 0.45). The mean MOCART score at follow-up was 62.6 points (range 30–95, SD 15.3). The results of the present study suggest that repair cartilage resulting from AMIC-aided repair of osteochondral lesions of the talus has a significantly lower glycosaminoglycan (GAG) content than normal hyaline cartilage, but can be regarded as having hyaline-like properties.

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Abstract 6

Title: Correlation of the R1 and R2 values of gadolinium-based MRI contrast media with the ΔHounsfield unit of CT contrast media of identical concentration

Authors: Seung-Man Yu, Seung-Hong Choi, Sae-Sark Kim, Eun-Hoe Goo, Youn-Sang Ji, Bo-Young Choe

Source: Current Applied Physics Volume 13, Issue 5, July 2013, Pages 857–863


Subjects:

Author Supplied Keywords: MRI contrast media; T1 pulse sequence; Signal to noise ratio; Relaxation time

Abstract: The optimal volume of contrast medium must be injected into the patient who emits the maximum signal intensity in an ROI. This study was investigated four different type MRI and one CT contrast agent in vitro and sought to establish relations between concentration, MRI relaxivity, CT Hounsfield unites selected kVp and different MRI T1 sequences. Using a CT contrast medium and four different MRI T1 contrast media, we developed five different phantom series. The MRI contrast media phantom was imaged on 1.5T and 3T MRI systems and measured the R1 and R2 value. A CT scanner was used to obtain images of the Iopromide 370 phantom with the quality of radiation to obtain images. The Pearson's correlation coefficient analyses were conducted between MRI CM phantom series with Iopromide 370 phantom. The non-parametric statistical analyses were performed for the values of kVp. The ΔHU of the test solution of the CT contrast media was produced in the same amount as the exponentially increased concentration of the MRI contrast media according to the increase in the dilution concentration, and was influenced by the quality of the X-ray. Through the results of this experiment that considered the two aforementioned factors, an image with a high diagnosis value can be acquired from the information on the concentration of the MRI T1 contrast media.

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Abstract 7

Title: Delayed gadolinium enhanced MRI of cartilage (dGEMRIC) can be effectively applied for longitudinal cohort evaluation of articular cartilage regeneration

Authors: J.E.J. Bekkers, L.W. Bartels, R.J. Benink, A.I. Tsuchida, K.L. Vincken, W.J.A. Dhert, L.B. Creemers, D.B.F. Saris

Source: Osteoarthritis and Cartilage Volume 21, Issue 7, July 2013, Pages 943–949


Subjects:

Author Supplied Keywords: dGEMRIC; Cartilage; Regeneration; Patient profiles

Abstract: Delayed gadolinium enhanced magnetic resonance imaging (MRI) of cartilage (dGEMRIC) facilitates non-invasive evaluation of the glycosaminoglycan content in articular cartilage. The primary aim of this study was to show that the dGEMRIC technique is able to monitor cartilage repair following regenerative cartilage treatment. Thirty-one patients with a focal cartilage lesion underwent a dGEMRIC scan prior to cartilage repair surgery and at 3 and 12 months follow-up. At similar time points clinical improvement was monitored using the Knee injury and Osteoarthritis Outcome Score (KOOS) and Lysholm questionnaires. Per MRI scan several regions-of-interest (ROIs) were defined for different locations in the joint. The dGEMRIC index (T1gd) was calculated for each ROI. Repeated-measures analysis of variance (RMANOVA) analysis was used to evaluate improvement in clinical scores and MRI T1gd over time. Also regression analysis was performed to show the influence of local repair on cartilage quality at distant locations in the knee. Clinical scores and the dGEMRIC T1gd per ROI showed a statistically significant improvement (P < 0.01), from baseline, at 12 months follow-up. Also, improvement from baseline in T1gd of the ROI defining the treated cartilage defect showed a direct relationship (P < 0.007) to the improvement of the T1gd of ROI at other locations in the joint. The dGEMRIC MRI protocol is a useful method to evaluate cartilage repair. In addition, local cartilage repair influenced the cartilage quality at other location in the joint. These findings validate the use of dGEMRIC for non-invasive evaluation of the effects of cartilage regeneration.

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Abstract 8

Title: In vivo comparison of delayed gadolinium-enhanced MRI of cartilage and delayed quantitative CT arthrography in imaging of articular cartilage

Authors: J. Hirvasniemi, K.A.M. Kulmala, E. Lammentausta, R. Ojala, P. Lehenkari, A. Kamel, J.S. Jurvelin, J. Töyräs, M.T. Nieminen, S. Saarakkala

Source: Osteoarthritis and Cartilage Volume 21, Issue 3, March 2013, Pages 434–442


Subjects:

Author Supplied Keywords: Articular cartilage; MRI; Contrast-enhanced computed tomography; Arthroscopy; Osteoarthritis; Knee joint

Abstract: To compare delayed gadolinium-enhanced magnetic resonance imaging (MRI) of cartilage (dGEMRIC) and delayed quantitative computed tomography (CT) arthrography (dQCTA) to each other, and their association to arthroscopy. Additionally, the relationship between dGEMRIC with intravenous (dGEMRICIV) and intra-articular contrast agent administration (dGEMRICIA) was determined. Eleven patients with knee pain were scanned at 3 T MRI and 64-slice CT before arthroscopy. dQCTA was performed at 5 and 45 min after intra-articular injection of ioxaglate. Both dGEMRICIV and dGEMRICIA were performed at 90 min after gadopentetate injection. dGEMRIC indices and change in relaxation rates (ΔR1) were separately calculated for dGEMRICIV and dGEMRICIA. dGEMRIC and dQCTA parameters were calculated for predetermined sites at the knee joint that were International Cartilage Repair Society (ICRS) graded in arthroscopy. dQCTA normalized with the contrast agent concentration in synovial fluid (SF) and dGEMRICIV correlated significantly, whereas dGEMRICIA correlated with the normalized dQCTA only when dGEMRICIA was also normalized with the contrast agent concentration in SF. Correlation was strongest between normalized dQCTA at 45 min and ΔR1,IV (rs = 0.72 [95% CI 0.56–0.83], n = 49, P < 0.01) and ΔR1,IA normalized with ΔR1 in SF (rs = 0.70 [0.53–0.82], n = 52, P < 0.01). Neither dGEMRIC nor dQCTA correlated with arthroscopic grading. dGEMRICIV and non-normalized dGEMRICIA were not related while ΔR1,IV correlated with normalized ΔR1,IA (rs = 0.52 [0.28–0.70], n = 50, P < 0.01). This study suggests that dQCTA is in best agreement with dGEMRICIV at 45 min after CT contrast agent injection. dQCTA and dGEMRIC were not related to arthroscopy, probably because the remaining cartilage is analysed in dGEMRIC and dQCTA, whereas in arthroscopy the absence of cartilage defines the grading. The findings indicate the importance to take into account the contrast agent concentration in SF in dQCTA and dGEMRICIA.

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Abstract 9

Title: Characterization of hyper intense nodules on T1-weighted liver magnetic resonance imaging: Comparison of Ferucarbotran-enhanced MRI with accumulation-phase FS-T1WI and gadolinium-enhanced MRI

Authors: Chen-Te Chou, Ran-Chou Chen, Wei-Tsung Chen, Jiunn-Ming Lii

Source: Journal of the Chinese Medical Association Volume 74, Issue 2, February 2011, Pages 62–68


Subjects:

Author Supplied Keywords: Dysplastic nodule; Ferucarbotran; Gadolinium; Hepatocellular carcinoma; T1-weighted hyper intense nodule

Abstract: T1-weighted (T1W) hyper intense nodules against a background of cirrhosis are diagnostically challenging in daily practice. All regenerative nodules, dysplastic nodules and hepatocellular carcinoma (HCC) might present hyper intense on T1W imaging (T1WI), so T1W hyper intense nodules cannot be definitively characterized as dysplastic nodules or HCC before biopsy, resection or transplantation. The purpose of our study was to evaluate Ferucarbotran-enhanced Magnetic Resonance Imaging (MRI) with accumulation-phase fat suppression T1-weighted imaging (FS-T1WI) in comparison with gadolinium-enhanced MRI for characterization of hyper intense nodules on unenhanced T1WI within cirrhotic liver. Two separate groups of patients with histologically-proven T1W hyper intense nodule on MRI were retrospectively identified. The Ferucarbotran group consisted of 17 T1W hyper intense nodules in 12 patients. The gadolinium group consisted of 22 T1W hyper intense nodules in 21 patients. All of the patients had liver cirrhosis. Finally, 11 HCC nodules, and six benign nodules were included in the Ferucarbotran group; 15 HCC nodules and seven benign nodules were included in the gadolinium group. With the conventional criteria, in the gadolinium-enhanced group, the sensitivity, specificity, and accuracy were 53%, 100%, and 73%, respectively. Using the conventional criteria in the Ferucarbotran group, the sensitivity, specificity, and accuracy were 73%, 100%, 82%, respectively. Using the conventional criteria plus hyper intense on the accumulation-phase FS-T1WI in the Ferucarbotran group for characterization of the T1W hyper intense nodules, the sensitivity, specificity, and accuracy were 100%, 83%, 94%, respectively. The sensitivity of Ferucarbotran-enhanced MR with accumulation-phase FS-T1WI was better than that of gadolinium-enhanced MRI (p = 0.01). Ferucarbotran-enhanced MRI with accumulation-phase FS-T1WI is superior to gadolinium-enhanced MRI in characterization of T1W hyper intense nodules within cirrhotic liver. T1W hyper intense nodule within cirrhotic liver depicting hyper intense on Ferucarbotran-enhanced accumulation-phase FS-T1WI should be investigated aggressively.

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Abstract 10

Title: Characterization of cryoinjury-induced infarction with manganese-and gadolinium-enhanced MRI and optical spectroscopy in pig hearts

Authors: Yanmin Yang, Jiankang Sun, Patricia Gervai, Marco L. Gruwel, Olga Jilkina, Eugene Gussakovsky, Xi Yang, Valery Kupriyanov

Source: Magnetic Resonance Imaging Volume 28, Issue 5, June 2010, Pages 753–766


Subjects:

Author Supplied Keywords: Acute and chronic cryoinjury; No-reflow embolization; Gd-enhanced MRI; Mn-enhanced MRI; Optical imaging and spectroscopy

Abstract: To investigate progression of cryoinjury in pigs using contrast-enhanced magnetic resonance imaging (MRI) as well as optical spectroscopy and imaging. Cryoinjury was produced in 16 pigs in vivo and investigated using Gd-and Mn-enhanced MRI, optical imaging/spectroscopy and histology in acute and chronic setting up to 4 weeks after the injury. (1) Acute cryoinjury resulted in formation of a lesion with a severely reduced rate of sub-epicardial indocyanine green (intravascular optical flow tracer) passage. In vivo late Gd-enhanced MRI showed a ∼10 mm deep hypointense area that was surrounded by a hyperintense rim while ex vivo Mn-enhanced MRI (MEMRI) detected a homogenous hypointense zone. Histological and spectroscopic examination revealed embolic erythrocytes blockages within the cryolesion with a thin necrotic rim neighboring the normal myocardium. (2) Chronic 4-week cryoinjury was characterized by uniform Gd-enhancement, whereas MEMRI revealed reduced Mn2+enhancement. Histological examination showed replacement of the cryoinjured myocardium by scar tissue. Acute cryoinjury resulted in formation of a no-reflow core embolized by erythrocytes and surrounded by a rim of necrotic tissue. Upon injury progression, the no-reflow zone shrunk and was completely replaced with scar tissue by 4 weeks after injury.

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Abstract 11

Title: The use of T2*-weighted multi-echo GRE imaging as a novel method to diagnose hepatocellular carcinoma compared with gadolinium-enhanced MRI: a feasibility study

Authors: Andrew D. Hardie, Peter B. Romano

Source: Magnetic Resonance Imaging Volume 28, Issue 2, February 2010, Pages 281–285


Subjects:

Author Supplied Keywords: Liver imaging; Hepatocellular carcinoma; T2*; Cirrhosis

Abstract: The goal of the study was to assess a T2*-weighted MRI sequence for the ability to identify hepatocellular carcinoma (HCC). Hepatic iron deposition, which is common in chronic liver disease (CLD), may increase the conspicuity of HCC on GRE imaging due to increased T2* signal decay in liver parenchyma. In this study, a breath-hold T2*-weighted MRI sequence was evaluated by a blinded observer for HCC and the results compared to a reference standard of gadolinium-enhanced MRI in these same patients. Forty-one patients (mean age 56.2 years; 17 females) were included in this approved, retrospective study. By the reference standard, 14 of 41 patients had a total of 25 HCCs. The sensitivity of the T2*-weighted MR sequence for identifying HCC, per lesion, was 60%, while the specificity was 100%. There was a significantly lower T2* value of liver parenchyma in patients with HCC identified by the T2*-weighted sequence than in those with HCCs which were not identified by the T2*-weighted sequence (27.8±2.2 vs. 21.9±2.1 ms; P=.02). A T2*-weighted MRI sequence can identify HCC in patients with CLD. This technique may be beneficial for imaging of patients contraindicated for gadolinium.

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Abstract 12

Title: Reproducibility of imaging human knee cartilage by delayed gadolinium-enhanced MRI of cartilage (dGEMRIC) at 1.5 Tesla

Authors: J. Multanen, E. Rauvala, E. Lammentausta, R. Ojala, I. Kiviranta, A. Häkkinen, M.T. Nieminen, A. Heinonen

Source: Osteoarthritis and Cartilage Volume 17, Issue 5, May 2009, Pages 559–564


Subjects:

Author Supplied Keywords: dGEMRIC; Reproducibility; Cartilage; Proteoglycan; Knee joint

Abstract: The purpose of this study was to investigate the day-to-day reproducibility of the delayed gadolinium-enhanced MRI of cartilage (dGEMRIC) measurement at different knee joint surfaces in healthy subjects at 1.5 Tesla (T). The dGEMRIC experiment was repeated for 10 asymptomatic volunteers three times with an average interval of 5 days between scans. The measurement was performed from a single sagittal slice through the center of the lateral femoral condyle and from the center of the patella in the axial plane. Cartilage was manually segmented into superficial, deep and full-thickness regions of interests (ROIs) at different topographical locations of the femur, tibia and patella. The reproducibility was evaluated separately for each ROI as well as for the entire bulk cartilage in the slice of each joint surface. The reproducibility at various ROIs expressed by root-mean-square average coefficient of variation (CVRMS) ranged between 4.7–12.9%. Thirty out of thirty-three ROIs showed a CVRMS less than 10%. Intraclass correlation coefficient (ICC) ranged between 0.45 and 0.98. The CVRMS and ICC for bulk dGEMRIC were 4.2% and 0.95 for femur, 5.5% and 0.87 for tibia, and 4.8% and 0.97 for patella. The dGEMRIC technique showed good day-to-day reproducibility, on the average 8% for small deep or superficial segments, 7% for full-thickness ROIs and 5% for bulk ROIs covering all visible cartilage in a single joint surface. We conclude that dGEMRIC imaging at field strength 1.5 T can be used as a reliable instrument for the assessment of articular cartilage when staff has been carefully trained.

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Abstract 13

Title: Gadolinium-Containing MRI Contrast Agents: Important Variations on a Theme for NSF

Author: Phillip H. Kuo, MD, PhD

Source: Journal of the American College of Radiology

Volume 5, Issue 1, January 2008, Pages 29–35


Subjects:

Author Supplied Keywords: Nephrogenic systemic fibrosis; nephrogenic fibrosing dermopathy; MRI contrast; gadolinium; kinetics; thermodynamics

Abstract: Millions of doses of gadolinium-based contrast agents (GBCAs) are administered annually to improve the clinical utility of magnetic resonance imaging. All the approved agents incorporate one atom of the rare earth metal gadolinium into a chelate to improve the safety of the ordinarily toxic free gadolinium. The undeniable epidemiologic link between GBCAs and nephrogenic systemic fibrosis (NSF) has prompted renewed investigation into the different chemical properties of the GBCAs despite their clinical interchangeability. Gadolinium-based contrast agents can be divided into different categories: linear versus macrocyclic structure, ionic versus nonionic, and non-protein-binding versus protein-binding agents. The GBCAs differ significantly with respect to transmetallation and kinetic and thermodynamic stability and therefore their propensity to release free gadolinium, which is hypothesized to induce NSF. That gadodiamide, with its susceptibility to transmetallation and relatively low thermodynamic and kinetic stability, is associated with the most cases of NSF supports this hypothesis. On the other hand, the greater stability of a macrocyclic agent hypothetically would confer a greater safety margin with regard to NSF. Because few published data on an experimental model of NSF exist, continuing vigilance is necessary to report new cases of NSF, especially with regard to the agents with small market share.

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Abstract 14

Title: Dynamic gadolinium-enhanced MRI in early ischaemia of the proximal femoral epiphysis – a preliminary study

Authors: X. Li, J. Qi, L. Xia, C. Yu, W. Peng, X. Hu, D. Hu



Subjects:


Abstract: To compare the sensitivities of dynamic Gadoteridol (Gd)-enhanced magnetic resonance imaging (MRI) and conventional Gd-enhanced spin-echo (SE) T1-weighted imaging (WI) in the detection of decreased perfusion of early epiphyseal ischaemia, and to determine the contribution of metaphyseal vascularity to physeal perfusion in epiphyseal vascular occlusion by dynamic Gd-enhanced MRI. Twenty-eight 2-week-old piglets were divided evenly into four groups: control groups A and B, and ischaemic groups A and B (seven animals in each). In the ischaemic groups, MRI was performed bilaterally on hips in persistent hyperabduction for 30 min. In the control and ischaemic group A the piglets underwent dynamic Gd-enhanced MRI, and in control and ischaemic group B the piglets were subjected to Gd-enhanced SE T1WI. In ischaemic group A, the enhancement ratio (ER) and enhancement speed (ES) of the various tissues (except the metaphysis) were significantly lower than those in control group A on dynamic Gd-enhanced MRI (p < 0.05). However, in ischaemic group B, no significant decrease in the ER of each tissue was found, compared with the ER in control group B as viewed using Gd-enhanced SE T1WI (p > 0.05). On dynamic Gd-enhanced MRI, the ER and ES of the physis were less than those of metaphysis in the ischaemic group A (p < 0.05); however, the ER and ES of the physis were similar to those of metaphysis in control group A (p > 0.05). Dynamic Gd-enhanced MRI is more sensitive than conventional Gd-enhanced SE T1WI in the detection of early epiphyseal ischaemia. Physeal perfusion might be from the metaphysis in epiphyseal vascular occlusion.

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Abstract 15

Title: Signal characteristic and enhancement patterns of pancreatic adenocarcinoma: evaluation with dynamic gadolinium enhanced MRI

Authors: H. Chandarana, J. Babb, M. Macari

Source: Clinical Radiology Volume 62, Issue 9, September 2007, Pages 876–883


Subjects:


Abstract: To determine the signal characteristics and enhancement patterns of proven pancreatic adenocarcinomas at 1.5 T and to compare these results with contrast enhanced computed tomography (CECT). Twenty-five patients, mean age 73 years, with proven pancreatic adenocarcinoma were imaged at 1.5 T using in- and opposed-phase, gradient-echo (GRE), T1-weighted sequences, T2 weighting using either a short tau inversion recovery (STIR) or frequency selective, fat-suppressed turbo spin echo (TSE) sequence, and with a three-dimensional (3D), fat-suppressed, GRE T1 sequence before, during the arterial, venous, and equilibrium phases after Gadolinium administration. Fourteen of the 25 patients underwent CECT. Magnetic resonance imaging (MRI) examinations were evaluated by two observers in consensus for size, signal characteristics, and enhancement patterns, and the results were compared with CECT. The mean size of pancreatic adenocarcinomas was 32 mm. On unenhanced T1-weighted images, 12 of 25 lesions (48%) were hypointense, 13 (52%) were isointense. On STIR/T2, 11 of 25 (44%) pancreatic adenocarcinomas were hyperintense, 14 (56%) were isointense. All 25 (100%) adenocarcinomas were hypointense during the arterial phase. Twenty (80%) and 17 (68%) remained hypointense in the venous phase and equilibrium phases, respectively. In seven of 14 (50%) cases, the pancreatic mass was iso-attenuating to the pancreatic parenchyma during both the pancreatic and venous phases of CECT. The results of the present study showed that all 25 pancreatic adenocarcinomas were hypointense to pancreatic parenchyma during the arterial phase. Moreover, MRI may be useful in patients with a high suspicion of pancreatic carcinoma that is not visualized during CECT.

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Abstract 16

Title: Diffuse dural gadolinium MRI enhancement associated with bilateral chronic subdural hematomas

Authors: Svetlana Blitshteyn, Laszlo L. Mechtler, Rohit Bakshi

Source: Clinical Imaging Volume 28, Issue 2, March–April 2004, Pages 90–92


Subjects:

Author Supplied Keywords: Magnetic resonance imaging; Brain; Gadolinium enhancement; Subdural hematoma

Abstract: Chronic subdural hematomas (CSDHs) typically present with cognitive dysfunction and a history of trauma. Localized dural enhancement on post contrast MRI scans associated with the surrounding membrane has been described in CSDH. We present an 83-year-old man with rapidly progressing cognitive dysfunction 4 weeks after head trauma related to a fall. MRI showed CSDHs, which in addition to localized dural gadolinium enhancement, showed a marked diffuse, symmetric, contiguous pachymeningeal enhancement of the supratentorial and infratentorial intracranial dural mater. Meningeal biopsy failed to disclose an infectious or neoplastic cause of the enhancement and instead showed fibrocollagenous change. We conclude that diffuse dural enhancement on MRI scans associated with CSDH cause does not necessarily indicate a superimposed process such as infection or malignancy. CSDH should be considered in the differential diagnosis of diffuse dural enhancement, especially when supported by appropriate clinical findings.

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Abstract 17

Title: Implications of post-gadolinium MRI results in 13 cases with posterior reversible encephalopathy syndrome

Authors: Mehmet Sahin Ugurel, Minako Hayakawa

Source: European Journal of Radiology Volume 53, Issue 3, March 2005, Pages 441–449


Subjects:

Author Supplied Keywords: Posterior reversible encephalopathy syndrome; Contrast-enhancement; Magnetic resonance imaging

Abstract: There is a relative lack of definitive information about the contrast-enhancement characteristics of lesions in posterior reversible encephalopathy syndrome (PRES). Evaluation of contrast-enhanced MRI findings in PRES with a special emphasis on pathophysiology of post-gadolinium behavior of these lesions. Contrast-enhanced 1.5 T MRI findings and relevant clinical data of the patients were retrospectively reviewed on 13 cases (six males, seven females; age range: 22–78; mean age 47). Although fluid attenuated inversion recovery (FLAIR) and diffusion-weighted MR images were considered for identification of the entity, primarily post-contrast T1-weighted MR images were searched for traces of enhancement in the lesions. No definitely enhancing lesion was identified in the MR images obtained in 6–48 h after onset of symptoms (mostly headaches, seizures and cortical visual field deficits) in this series. Severity of disease indicated by small hemorrhages, confluence of lesions or progression to cytotoxic edema did not seem to alter this result. Typical lesion characteristics were consistent with vasogenic edema on FLAIR and diffusion MR images. Acute elevation of blood pressure on chronic hypertensive background was responsible in four, eclampsia in three, uremia with blood pressure fluctuations in three, and cyclosporine-toxicity in three cases. Although occasional enhancing brain lesions have been reported in the literature on PRES, contrast-enhancement of lesions may be a factor of scan timing and underlying etiology. Prospective studies with larger series on PRES are required for better evaluation of contrast-enhancement in MRI with respect to scan timing, which in turn may help understand its pathophysiology better.

17

Abstract 18

Title: Gadolinium-enhanced MRI in the evaluation of minimally invasive treatments of the prostate: correlation with histopathologic findings

Authors: Benjamin T Larson, Joseph M Collins, Christian Huidobro, Alberto Corica, Santiago Vallejo, David G Bostwick

Source: Urology Volume 62, Issue 5, November 2003, Pages 900–904


Subjects:


Abstract: To explore the use of magnetic resonance imaging (MRI) with gadolinium enhancement as a noninvasive method to image the extent of ablation after minimally invasive treatment. Minimally invasive methods for ablating prostatic tissue have emerged as a viable option in the treatment of prostate disease. As these devices enter the mainstream of patient care, imaging methods that verify the exact location, extent, and pattern of the ablation are needed. Nineteen patients with prostate cancer were evaluated. All received some type of minimally invasive treatment, post-treatment gadolinium-enhanced MRI sequences, and radical retropubic prostatectomy for histopathologic evaluation. Visual comparisons of gadolinium defects and areas of coagulation necrosis as seen on histopathologic evaluation were made by us. Volumetric and two-dimensional area measurements of the ablation lesions were also compared for correlation between the MRI and histopathologic results. Gadolinium-enhanced MRI could be matched to histopathologic findings by visual comparison in 17 of the 19 cases. Surgically distorted histopathologic specimens and a small periurethral lesion caused 2 patients to have MRI and histopathologic results that could not be matched. Complete volumetric measurements were available for 16 of the 19 patients and correlated strongly (r = 0.924). The two-dimensional area data for all patients also showed significant correlation (r = 0.886). Correlation with histopathologic findings showed gadolinium-enhanced MRI to be useful for determining the location, pattern, and extent of necrosis caused within the prostate by minimally invasive techniques. Gadolinium-enhanced MRI gives the urologist a useful tool to evaluate the effectiveness of new minimally invasive therapies.

18

Abstract 19

Title: An investigation of the toxicity of gadolinium based MRI contrast agents using neutron activation analysis

Authors: M.E Bartolini, J Pekar, D.R Chettle, F McNeill, A Scott, J Sykes, F.S Prato, G.R Moran



Subjects:

Author Supplied Keywords: Gadolinium; Magnetic resonance imaging; Contrast agents; Toxicity; Neutron activation analysis

Abstract: The toxicity of gadolinium (Gd) based MRI contrast agents, is based upon the amount of Gd that dissociates from its chelate and deposits in tissues. In this study, the toxicities of two contrast agents were tested using different injection strategies in two animal models. Following a bolus injection of 0.2 mmol/kg of Gd-DTPA in a pilot study with a single canine, Gd levels were as high as 2.05 ± 0.17 ppm and 0.47 ± 0.11 ppm 2 weeks post injection in the kidney and liver tissues, respectively. To evaluate the role that the injection strategy plays in toxicity, 0.8 mmol/kg of Gd-(HP-DO3A) was injected into rats, in a second study, via bolus and constant infusion techniques. Gd was only detected in the kidney in the bolus injected rats but in the lung as well in the constant infusion injected rats. Concentrations detected in the kidney for both strategies, were comparable within error: 1.37 ± 0.46 ppm for the bolus and 1.24 ± 0.39 ppm for the bolus/constant infusion strategy and 0.16 ± 0.14 ppm in the lung for the constant infusion technique. The contrast infusion technique does not appear to present an increased risk of toxicity over the bolus technique except perhaps to a small degree in the lung.

19

Abstract 20

Title: 3D Gadolinium-enhanced MRI Venography: Evaluation of Central Chest Veins and Impact on Patient Management

Authors: J.W. Oxtoby, E. Widjaja, K.M. Gibson, K. Uzoka

Source: Clinical Radiology Volume 56, Issue 11, November 2001, Pages 887–894


Subjects:

Author Supplied Keywords: gadolinium, magnetic resonance imaging (MRI), vascular studies, venous access, venous stenosis, obstruction

Abstract: To assess the value of a simplified 3D gadolinium-enhanced magnetic resonance imaging (MRI) venography for central chest veins. In this retrospective study of 24 patients, the MRI findings and medical records were reviewed to determine whether MRI results correlated with subsequent findings, and to determine the effect on clinical management. 3D steady state gradient-echo sequence, fast imaging with steady state precession (FISP), was used. We employed a simplified protocol not requiring bolus timing or subtraction to achieve rapid data acquisition and hence good compliance in this group of frail patients. Following intravenous administration of a bolus of gadolinium, two acquisitions were obtained in order to ensure adequate opacification of all veins. Individual partitions and maximum intensity projections were then analyzed to determine whether the veins were patent, stenosed or occluded. The indications for MRI were to assess the patency of central veins for the purpose of cannulation or arteriovenous fistula formation in 17 patients. Out of the 12 patients who proceeded to an intervention, MRI venography successfully predicted an appropriate site in 10 patients. In the remaining seven patients, MRI venography was valuable in confirming or excluding the clinical suspicion of central venous thrombosis and directly influenced the management in five patients. 3D gadolinium-enhanced MRI venography is a valuable means of providing a global representation of the central venous system and guiding subsequent central venous cannulation.

20

Abstract 21

Title: The diagnostic role of gadolinium enhanced MRI in distinguishing between acute medullary bone infarct and osteomyelitis

Authors: Hilary Umans, Nogah Haramati, Gideon Flusser

Source: Magnetic Resonance Imaging Volume 18, Issue 3, April 2000, Pages 255–262


Subjects:

Author Supplied Keywords: Medullary bone infarct; Osteonecrosis; Osteomyelitis; Sickle cell disease; Systemic lupus erythematosus

Abstract: The objective of the study was to evaluate the diagnostic utility of contrast enhanced magnetic resonance imaging (MRI) for distinguishing between acute medullary bone infarct and osteomyelitis. There were 11 patients (age 6–34 years) presented to our institution between December 1994 and February 1998 with a clinical differential diagnosis of acute bone infarct versus osteomyelitis and inconclusive radiographs were imaged using MRI. All but one received i.v. gadolinium. Nine of the patients had homozygous Sickle Cell disease (SCD) and two had Systemic Lupus Erythematosus (SLE), the latter requiring chronic methylprednisolone. Osteomyelitis was confirmed either by biopsy alone or by the combination of Gallium67 scan in conjunction with positive blood cultures and clinical resolution following antibiotics. Infarcts without osteomyelitis were confirmed either by biopsy or resolution of symptoms without antibiotic therapy. All patients had at least six months clinical follow-up. The results found that seven of nine patients with SCD had acute infarct only. One patient with SCD had osteomyelitis only. Three patients (two SLE and one SCD) had both acute-on-chronic infarcts and superimposed osteomyelitis, one with an adjacent soft tissue abscess. Accurate distinction between infarct and osteomyelitis was impossible for one patient with SLE who did not receive contrast. All other cases were correctly diagnosed prospectively based on distinct patterns of MRI contrast enhancement. In all adult patients, acute infarcts demonstrated thin, linear rim enhancement on MRI while osteomyelitis revealed more geographic and irregular marrow enhancement. Two of four cases of osteomyelitis also demonstrated subtle cortical defects with abnormal signal traversing marrow and soft tissue. The single pediatric patient demonstrated elongated, serpiginous central medullary enhancement with periostitis. We concluded that the pattern of MR contrast enhancement may allow accurate distinction between acute infarct and osteomyelitis, or recognition of osteomyelitis superimposed on bone infarction.

21

Abstract 22

Title: Differential diagnosis of hepatic tumors with delayed enhancement at Gadolinium- enhanced MRI

Authors: Hitomi Awaya, MD, Katusyoshi Ito, MD, Kazumitsu Honjo, MD, Takeshi Fujita, MD, Tsuneo Matsumoto, MD, Naofumu Matsunaga, MD

Source: Clinical Imaging Volume 22, Issue 3, May–June 1998, Pages 180–187


Subjects:

Author Supplied Keywords: Liver, MR; Liver neoplasms, MR; Liver neoplasms, diagnosis; Liver neoplasms, delayed enhancement

Abstract: Hepatic lesions with delayed enhancement are sometimes encountered on gadolinium-enhanced MRI of the liver. This study illustrates the varied appearances of several pathologic entities with delayed enhancement, including hepatic hemangioma, hepatic metastases, intrahepatic cholangiocarcinoma, focal nodular hyperplasia, hepatic abscess, hepatocellular carcinoma, and hepatocellular carcinoma after trans catheter arterial chemoembolization, and presents the utility of arterial-phase dynamic MRI in the differential diagnosis of these lesions. Possible causes of these delayed enhancements are also discussed.

22

Abstract 23

Title: High CD6 and low chemokine receptor expression on peripheral blood lymphocytes correlates with MRI gadolinium enhancement in MS

Authors: Anna Jurewicz, Krzysztof Zaleski, Malgorzata Domowicz, Krzysztof Selmaj

Source: Journal of Neuroimmunology Volume 276, Issues 1–2, 15 November 2014, Pages 187–194


Subjects: CD6 mRNA correlates with the number and size of Gd+ lesions.

Gd+ lesion correlates with increased CD6 and decreased CCRs expression on PB T cells.

Co-expression of CD6 with CCR1 and CCR5 predisposes T cells for migration into CSF.

Author Supplied Keywords: Multiple sclerosis (MS); CD6; Peripheral mononuclear cells (PBMC); MRI; Gadolinium enhancing lesion; Chemokine receptors

Abstract: Correlation between gadolinium-enhancing [Gd(+)] lesions on MRI and expression of CD6 molecules and a group of chemokine receptors on peripheral blood (PB) and cerebrospinal fluid (CSF) immune cells was measured in multiple sclerosis (MS) patients. Twenty remitting–relapsing MS patients with (n = 10) and without (n = 10) Gd(+) lesions entered the study. mRNA and surface expression of CD6 and CCR1, CCR2, CCR3 and CCR5 was measured by immunostaining and flow cytometry. Expression of mRNA and surface staining for CD6 in PB T lymphocytes was increased in Gd(+) compared to Gd(–) patients (p < 0.01; p < 0.05, respectively). CD6 mRNA correlated with the number and size of Gd(+) lesions (r = 0.67, and r = 0.65 respectively). mRNA and surface expression for CCR1, CCR2, and CCR3 in PB cells was lower in Gd(+) compared to Gd(–) MS patients (p < 0.05, p < 0.05). The frequency of cells co-expressing CD6 with CCR1 and CCR5 was low in PB T lymphocytes and high in CSF (p < 0.05, p < 0.05). These results suggest that Gd(+) correlates with increased expression of CD6 and decreased expression of chemokine receptors on PB T lymphocytes. Co-expression of CD6 with CCR1 and CCR5 predisposes cells for transmigration into CSF.

23

Abstract 24

Title: Computed model of gadolinium enhanced MRI of breast disease

Authors: Philip J. Kenney, Wlad T. Sobol, J. Kevin Smith, Desiree E. Morgan

Source: European Journal of Radiology Volume 24, Issue 2, February 1997, Pages 109–119


Subjects:

Author Supplied Keywords: MRI; Breast cancer; Gadolinium

Abstract: Investigation has shown that the most useful MRI finding for the detection of breast cancer is enhancement following intravenous contrast. However, many widely different imaging protocols have been used. The purpose of this study is to explicate factors that affect the signal intensity of breast lesions after intravenous gadolinium. A computer model was developed using equations based on published data. The effect of gadolinium on breast tissues was calculated using the model with appropriate values for baseline tissue relaxation times, relaxivity of gadolinium at the given field strength and concentration of gadolinium based on published data, for the TR, TE, flip angle and field strength of several published sequences used for enhanced breast MRI. The computer model allows comparison of the performance of different sequences, which can be displayed graphically. These vary in their performance, largely dependent on T1 weighting. Enhancement is also affected by the baseline of the T1 of the lesion and sensitivity of the sequence to gadolinium. Malignant lesions demonstrate greater observed enhancement than predicted when assuming symmetric distribution of contrast, indicating there is greater accumulation of gadolinium, accounting for the differential enhancement between benign and malignant lesions. MRI sequences vary greatly in their demonstration of enhancement after intravenous gadolinium contrast. Numerical diagnostic criteria such as % signal intensity change must be interpreted with care when using a different sequence than that on which the criterion was developed. There is preferentially greater accumulation of contrast in malignant lesions, whether due to angiogenesis or altered permeability.

24

Abstract 25

Title: Defining the use of gadolinium enhanced MRI in the assessment of the postoperative lumbar spine

Authors: L.S. Wilkinson, E. Elson, A. Saifuddin, A.O. Ransford

Source: Clinical Radiology Volume 52, Issue 7, July 1997, Pages 530–534


Subjects:


Abstract: A retrospective study of case notes and magnetic resonance imaging (MRI) examinations was performed to assess the value of gadolinium enhanced MRI in the investigation of persistent back pain following lumbar spine surgery in patients who have not had a discectomy for disc herniation. Gadolinium enhancement is commonly used during MRI of patients with persistent back pain following surgery and epidural scar is frequently identified in patients who have had a previous discectomy. However the value of gadolinium enhancement in patients without previous discectomy had not been addressed. One hundred sets of case notes were examined and 24 patients with an accurate history of previous lumbar spine surgery without discectomy were identified. The nature of surgery and the MRI findings were correlated in these patients. Epidural enhancement was identified at seven sites in six patients (engorged epidural venous plexus, three; enhancement adjacent to degenerate discs, two; enhancement adjacent to facets, two). In no case was epidural scarring involving nerve roots identified. We conclude that routine gadolinium enhancement is unnecessary in patients without a history of discectomy for disc herniation.

25

Abstract 26

Title: Dynamic sequential 3D gadolinium-enhanced MRI of the whole breast

Authors: Elisabeth V. Heiberg, William H. Perman, Virginia M. Herrmann, Christina G. Janney, M.D.

Source: Magnetic Resonance Imaging Volume 14, Issue 4, 1996, Pages 337–348


Subjects:

Author Supplied Keywords: Contrast-enhanced 2D MR imaging; Breast lesions; Sequential 3D gadolinium-enhanced MRI

Abstract: Dynamic contrast-enhanced 2D MR imaging of the breast has shown high sensitivity and specificity for the detection and characterization of breast lesions. We investigated the ability of a dynamic fast 3D MR imaging technique that repeatedly scans the whole breast in 44-s intervals without an interscan delay time to obtain similar sensitivity and specificity as 2D imaging. Fifty-six patients scheduled for breast biopsy were entered into the study, and 83 lesions detected by 3D dynamic scanning were biopsied. Dynamic 3D contrast-enhanced breast imaging with subtraction detected and correctly classified all 23 cancers, and 44 of the 60 benign lesions yielding a sensitivity of 100%, a specificity of 73%, and a 100% predictive negative value. The enhancement profiles of metastatic lymph nodes were similar to those of primary cancer. This technique allowed detection of multifocal and multicentric lesions and did not require a priori knowledge of lesion location. These results indicate that dynamic contrast-enhanced 3D MRI of the whole breast is a useful and economically feasible method for staging breast cancer, providing a comprehensive noninvasive method for total evaluation of the breast and axilla in patients considering breast conservation surgery or lumpectomy.

26

Abstract 27

Title: Gadolinium-enhanced MRI of the abnormal prostate

Authors: F.Graham Sommer, Hanh V. Nghiem, Robert Herfkens, John McNeal



Subjects:

Author Supplied Keywords: Magnetic resonance (MR); Contrast enhancement; Prostate; Neoplasms; Magnetic resonance (MR) tissue characterization

Abstract: A prospective study of the use of a low osmolar gadolinium-based intravenous contrast material for MRI of the abnormal prostate was performed. Eight patients scheduled for prostatectomy, six with prostate cancer and two with benign prostatic hyperplasia (BPH), were imaged preoperatively on a 1.5 T system using a pelvic coil array and employing Gadodiamide (0.3 mmol/kg). T2-weighted fast-spin echo (FSE) imaging was also performed in the same axial planes employed for gadolinium-enhanced studies. Detailed pathologic correlation was performed for the six patients with carcinoma. While regions of BPH and cancer enhanced to a similar degree following intravenous contrast agent, BPH enhancement was more heterogeneous than cancer. No advantages in detecting prostate cancer, in differentiating cancer from BPH or normal prostatic tissue, or in assessing extra-prostatic spread of cancer were observed for the contrast-enhanced studies compared to T2-weighted FSE imaging.

27

Abstract 28

Title: MRI gadolinium enhancement precedes neuroradiological findings in acute necrotizing encephalopathy

Authors: Takeshi Yoshida, Takuya Tamura, Yuhki Nagai, Hiroyuki Ueda, Tomonari Awaya, Minoru Shibata, Takeo Kato, Toshio Heike

Source: Brain and Development Volume 35, Issue 10, November 2013, Pages 921–924


Subjects:

Author Supplied Keywords: Acute necrotizing encephalopathy; Magnetic resonance imaging; Gadolinium enhancement; Pathogenesis; Cytokine storm

Abstract: We report a 2-year-old Japanese boy with acute necrotizing encephalopathy (ANE) triggered by human herpes virus-6, who presented insightful magnetic resonance imaging (MRI) findings. He was admitted due to impaired consciousness and a convulsion, 2 days after the onset of an upper respiratory infection. At admission, cranial MRI showed marked gadolinium enhancement at the bilateral thalami, brainstem and periventricular white matter without abnormal findings in noncontrast MRI sequences. On the following day, noncontrast computed tomography demonstrated homogeneous low-density lesions in the bilateral thalami and severe diffuse brain edema. The patient progressively deteriorated and died on the 18th day of admission. The pathogenesis of ANE remains mostly unknown, but it has been suggested that hypercytokinemia may play a major role. Overproduced cytokines cause vascular endothelial damage and alter the permeability of the vessel wall in the multiple organs, including the brain. The MRI findings in our case demonstrate that blood–brain barrier permeability was altered prior to the appearance of typical neuroradiological findings. This suggests that alteration of blood–brain barrier permeability is the first step in the development of the brain lesions in ANE, and supports the proposed mechanism whereby hypercytokinemia causes necrotic brain lesions. This is the first report demonstrating MRI gadolinium enhancement antecedent to typical neuroradiological findings in ANE.

28

Abstract 29

Title: Neurosarcoidosis: Correlation of cerebrospinal fluid findings with diffuse leptomeningeal gadolinium enhancement on MRI and clinical disease activity

Authors: Oliver Wengert, Eva Rothenfusser-Korber, Boris Vollrath, Georg Bohner, Franziska Scheibe, Carolin Otto, Jörg Hofmann, Klemens Angstwurm, Klemens Ruprecht

Source: Journal of the Neurological Sciences Volume 335, Issues 1–2, 15 December 2013, Pages 124–130


Subjects:

Author Supplied Keywords: Sarcoidosis; Neurosarcoidosis; Cerebrospinal fluid; MRI; Gadolinium; Leptomeningeal enhancement

Abstract: Cerebrospinal fluid (CSF) examination is considered important in the diagnosis of neurosarcoidosis, however, data on whether and how CSF parameters may be related to MRI findings and clinical disease activity of patients with neurosarcoidosis are scarce. To correlate CSF findings in patients with neurosarcoidosis with MRI findings and clinical disease activity. Results of 51 comprehensive CSF examinations of 25 patients with probable or definite neurosarcoidosis according to the Zajicek-criteria were analyzed retrospectively. Patients with diffuse leptomeningeal gadolinium enhancement on MRI had significantly higher cell counts (≥ 50 cells/μl in 80%), total protein (≥ 200 mg/dl in 80%), CSF/serum albumin quotients (QAlb, ≥ 30 in 80%), and lactate (≥ 30 mg/dl in 70%), but significantly lower glucose levels (≤ 40 mg/dl in 67%) than patients without leptomeningeal enhancement. Irrespective of MRI findings, activated lymphocytes and plasma cells were detected in the initial CSF examination in 60% and 47% of patients, and an intrathecal synthesis of IgG, IgA, and IgM in 22%, 29%, and 22%. Patients with clinically active disease had significantly higher CSF cell counts, total protein, QAlb, and lactate, but significantly lower glucose levels than patients with stable disease. CSF abnormalities in neurosarcoidosis are most pronounced in patients with diffuse leptomeningeal enhancement on MRI. CSF analyses may thus aid in the distinction of different radiographic and pathologic manifestations of neurosarcoidosis. Furthermore, CSF examinations may allow monitoring disease activity in patients with neurosarcoidosis.

29

Abstract 30

Title: Feasibility of free-breathing late gadolinium-enhanced cardiovascular MRI for assessment of myocardial infarction: Navigator-gated versus single-shot imaging

Authors: Hidenari Matsumotoa, Tetsuya Matsuda, Kenichi Miyamoto, Kenji Nakatsuma, Masataka Sugahara, Toshihiko Shimada

Source: International Journal of Cardiology Volume 168, Issue 1, 20 September 2013, Pages 94–99


Subjects: BH, breath-hold; CMR, cardiovascular magnetic resonance; LGE, late gadolinium-enhanced; LV, left ventricle/ventricular; MI, myocardial infarction; NAV, navigator-gated; SDNR, signal difference-to noise ratio; SI, signal intensity; SNR, signal-to-noise ratio; SS, single-shot‐

Author Supplied Keywords: Free-breathing; Late gadolinium-enhanced magnetic resonance imaging; Myocardial infarction; Navigator-gated; Single-shot

Abstract: The aim of this study was to evaluate the feasibility of two free-breathing late gadolinium-enhanced cardiovascular magnetic resonance (LGE-CMR) techniques (two-dimensional segmented navigator-gated [NAV-LGE] and single-shot [SS-LGE]) by comparing with breath-hold LGE-CMR (BH-LGE) as reference. A total of 200 consecutive patients underwent the three LGE-CMR imaging techniques. BH patterns were assessed with dynamic navigator MR imaging. Image quality was graded on a 5-point scale (4 = optimal; 0 = not assessable). In patients with sufficient BH capability (diaphragmatic movement with a deviation of < 3 mm), hyper enhancement was scored with a 5-point scale, and global infarct size (%left ventricle) was quantified. Compared to free-breathing LGE-CMR, BH-LGE had higher image quality grade in patients with sufficient BH capability (P < 0.01 [vs. NAV-LGE]; P < 0.001 [vs. SS-LGE]) but poorer image quality in patients with insufficient BH capability (P < 0.001 [vs. NAV-LGE]; P < 0.01 [vs. SS-LGE]). NAV-LGE had higher sensitivity for infarct detection than SS-LGE (97.1% vs. 88.4%, P < 0.05), but specificity was not significantly different (97.3% vs. 94.7%, P = 0.37). By Bland–Altman analysis, the average differences in global infarct size were 0.4% and 1.2%, and the limits of agreement were ± 4.0% and ± 5.9% for NAV- and SS-LGE, respectively. Although both NAV- and SS-LGE improve the image quality in patients with insufficient BH capability, NAV-LGE is superior to SS-LGE in infarct detection and infarct size measurement. NAV-LGE can be a possible first-line technique for patients with inability to perform sufficient BH.

30

Abstract 31

Title: Gadolinium-based contrast agents targeted to amyloid aggregates for the early diagnosis of Alzheimer's disease by MRI

Authors: Guillaume Borta, Sarah Catoen, Hélène Borderies, Adel Kebsi, Sébastien Ballet, Gaëlle Louin, Marc Port, Clotilde Ferroud

Source: European Journal of Medicinal Chemistry Volume 87, 24 November 2014, Pages 843–861


Subjects: Syntheses of MRI Gd-based contrast agents (CAs) targeted on the Aβ aggregates.

Identification of structural modifications to improve water solubility of the CAs.

Identification of structural modifications to improve amyloid binding of the CAs.

Evaluation of blood–brain barrier crossing of the CAs.

Complete study of a new family of MRI CAs for the diagnosis of Alzheimer's disease.

Author Supplied Keywords: Alzheimer's disease; Amyloid; Gadolinium; DOTA; Pyridine containing TriAza (PCTA); Magnetic resonance imaging (MRI)

Abstract: While important efforts were made in the development of positron emission tomography (PET) tracers for the in vivo molecular diagnosis of Alzheimer's disease, very few investigations to develop magnetic resonance imaging (MRI) probes were performed. Here, a new generation of Gd(III)-based contrast agents (CAs) is proposed to detect the amyloid β-protein (Aβ) aggregates by MRI, one of the earliest biological hallmarks of the pathology. A building block strategy was used to synthesize a library of 16 CAs to investigate structure–activity relationships (SARs) on physicochemical properties and binding affinity for the Aβ aggregates. Three types of blocks were used to modulate the CA structures: (i) the Gd(III) chelates (Gd(III)-DOTA and Gd(III)-PCTA), (ii) the biovectors (2-arylbenzothiazole, 2-arylbenzoxazole and stilbene derivatives) and (iii) the linkers (neutrals, positives and negatives with several lengths). These investigations revealed unexpected SARs and a difficulty of these probes to cross the blood–brain barrier (BBB). General insights for the development of Gd(III)-based CAs to detect the Aβ aggregates are described.

31

Abstract 32

Title: Prognostic value of adenosine stress perfusion cardiac MRI with late gadolinium enhancement in an intermediate cardiovascular risk population

Authors: Angela G. Bertaso, James D. Richardson, Dennis T.L. Wong, Michael S. Cunnington, Adam J. Nelsona, Hussam Tayeba, Kerry Williams, Derek P. Chew, Matthew I. Worthley, Karen S.L. Teo, Stephen G. Worthley

Source: International Journal of Cardiology Volume 167, Issue 5, 1 September 2013, Pages 2055–2060


Subjects:

Author Supplied Keywords: Cardiac magnetic resonance; Stress perfusion; Adenosine; Prognosis; Ischemia; Intermediate risk

Abstract: The high diagnostic accuracy of adenosine stress cardiac magnetic resonance (AS-CMR) for detecting coronary artery stenosis, with high sensitivity and specificity, is well documented. Prognostic data, particularly in non-low risk study populations and for greater than 12 months of follow up, is however lacking or variable in its findings. We present prognostic data, in an intermediate cardiovascular risk cohort undergoing adenosine stress perfusion CMR, over approximately 2 years of follow up. The study population comprised 362 patients referred for a clinically indicated stress CMR and included patients with proven coronary artery disease (CAD; n = 157) or unknown CAD status, yet an intermediate cardiovascular risk profile (n = 205). Perfusion imaging was performed at stress (adenosine 140 μg/kg/min) and rest on a 1.5 T system. Patient records and state-wide hospital databases were reviewed. Major adverse cardiac events — death, myocardial infarction, revascularization or ischemic hospitalization — were evaluated over a median follow up of 22 months. Of the 362 cases, 90 had a stress perfusion CMR positive for ischemia and experienced a MACE rate of 24%. Of the 272 negative CMR scans, 225 were also negative for late gadolinium enhancement, and in this group MACE was encountered in only 6 (2.7%) patients. Accordingly a negative stress CMR afforded a freedom from MACE of 97.3%. Freedom from death/myocardial infarction was 99.6%. In patients with confirmed coronary artery disease or at intermediate risk for cardiovascular events, a negative stress perfusion CMR is associated with an excellent prognosis over nearly 2 years of follow up.

32

Abstract 33

Title: A self-assembly heterotrinuclear gadolinium (III)–iron (II) complex as a MRI contrast agent

Authors:

Source: Inorganic Chemistry Communications Volume 14, Issue 12, December 2011, Pages 1898–1900


Subjects:

Author Supplied Keywords: Gadolinium; Self-assembly; MRI; Relaxivity; Contrast agent

Abstract: A new self-assembly gadolinium(III)–iron(II) complex (Gd2Fe) was synthesized and characterized. Relaxivity studies showed that complex Gd2Fe exhibited higher relaxation efficiency compared with the clinically used Gd-DTPA. In vitro MR images on a 0.5 T magnetic field exhibited a remarkable enhancement of signal contrast for Gd2Fe than Gd-DTPA. The results indicated that Gd2Fe could serve as a potential MRI contrast agent. A self-assembly Gd(III)–Fe(II) complex (Gd2Fe) was synthesized and characterized. It exhibited higher relaxation efficiency than the clinically used Gd-DTPA. A remarkable enhancement of signal contrast was found in vitro MR images. Gd2Fe complex could serve as a potential MRI contrast agent.

33

Abstract 34

Title: Effective encapsulation of a new cationic gadolinium chelate into apoferritin and its evaluation as an MRI contrast agent

Authors: Akira Makino, PhD, Hiroshi Harada, PhD, Tomohisa Okada, MD, PhD, Hiroyuki Kimura, PhD, Hiroo Amano, PhD, Hideo Saji, PhD, Masahiro Hiraoka, MD, PhD, Shunsaku Kimura, PhD

Source: Nanomedicine: Nanotechnology, Biology and Medicine Volume 7, Issue 5, October 2011, Pages 638–646


Subjects:

Author Supplied Keywords: Magnetic resonance imaging; Molecular imaging; Apoferritin; Drug delivery; Gadolinium complex

Abstract: Gd-Me2DO2A with a T1 proton relaxivity twice as high as that of commercial Gd-DOTA was newly designed and synthesized. Me2DO2A kept its high association property with gadolinium ions (Gd3+), and the Gd-Me2DO2A was efficiently encapsulated into the apoferritin cavity to further enhance the T1 relaxivity as much as 10-fold higher than Gd-DOTA on a Gd basis. The high T1 relaxivity was attained by (i) increased accessibility of water molecules to Gd3+ ions in the chelate and (ii) macromolecular effect of the encapsulation. By the surface modification of apoferritin with dextran, in vivo blood clearance time of apoferritin could be prolonged. Magnetic resonance imaging of tumor-bearing mice showed that the apoferritin contrast agent accomplished tumor detection effectively as a bright signal as a result of the enhanced permeation and retention effect. Single-dose toxicity test showed no serious side effects. The apoferritin-encapsulated Gd is therefore a possible candidate for a new magnetic resonance imaging contrast agent.

34

Abstract 35

Title: Optimizing dose and administration regimen of a high-relaxivity contrast agent for myocardial MRI late gadolinium enhancement

Authors: Francesco Secchi, Giovanni Di Leo, Giacomo D.E. Papini, Francesca Giacomazzi, Marisa Di Donato, Francesco Sardanelli

Source: European Journal of Radiology Volume 80, Issue 1, October 2011, Pages 96–102


Subjects:

Author Supplied Keywords: Cardiac magnetic resonance; Contrast-to-noise ratio; Dose finding; Late gadolinium enhancement; Myocardial infarction

Abstract: To investigate the time-course of late gadolinium enhancement of infarcted myocardium using gadobenate dimeglumine at different dosages and administration regimens. After institutional review board approval and informed consent, we studied 13 patients (aged 63 ± 11 years) with chronic myocardial infarction. They underwent two gadobenate dimeglumine-enhanced MR examinations (interval 24–48 h) using short-axis inversion-recovery gradient-echo sequences, with the following two different protocols, in randomized order: 0.05 mmol/kg and imaging at the 2.5th, 5th, 7.5th and 10th minute plus 0.05 mmol/kg and imaging at the 12.5th, 15th, 17.5th and 20th minute; the same as before but using 0.1 mmol/kg for both contrast injections. Contrast-to-noise ratios (CNRs) between infarcted myocardium, non-infarcted myocardium and left ventricle cavity were calculated for each time-point (2.5-min steps). Friedman ANOVA was used for comparing the CNR time-course; Wilcoxon test for comparing CNR at the 10th and the 20th minute. The CNR between infarcted and non-infarcted myocardium obtained at the 20th minute with 0.05 plus 0.05 mmol/kg resulted significantly higher than that obtained at the 10th minute with 0.05 mmol/kg (P = 0.033) while not significantly different from that obtained at the 10th (0.1 mm/kg) or at the 20th minute with 0.1 plus 0.1 mmol/kg. The CNR between infarcted myocardium and the left ventricle cavity obtained at the 20th minute with 0.05 plus 0.05 mmol/kg resulted significantly higher than all other measured values (P ≤ 0.017). Using gadobenate dimeglumine, 0.05 plus 0.05 mmol/kg allows for a higher CNR between infarcted myocardium and the left ventricle cavity allowing for reliable assessment of the sub-endocardial infarctions.

35

Abstract 36

Title: Accumulation of MRI contrast agents in malignant fibrous histiocytoma for gadolinium neutron capture therapy

Authors: T. Fujimoto, H. Ichikawa, T. Akisue, I. Fujita, K. Kishimoto, H. Hara, M. Imabori, H. Kawamitsu, P. Sharma, S.C. Brown, B.M. Moudgil, M. Fujii, T. Yamamoto, M. Kurosaka, Y. Fukumori

Source: Applied Radiation and Isotopes Volume 67, Issues 7–8, Supplement, July 2009, Pages S355–S358


Subjects:

Author Supplied Keywords: Gadolinium NCT; Chitosan; Nanoparticle; GD-DTPA; Malignant fibrosis histiocytoma (MFH); Enhanced magnetic resonance imaging (MRI)

Abstract: Neutron-capture therapy with gadolinium (Gd-NCT) has therapeutic potential, especially that gadolinium is generally used as a contrast medium in magnetic resonance imaging (MRI). The accumulation of gadolinium in a human sarcoma cell line, malignant fibrosis histiocytoma (MFH) Nara-H, was visualized by the MRI system. The commercially available MRI contrast medium Gd-DTPA (Magnevist®, dimeglumine gadopentetate aqueous solution) and the biodegradable and highly gadopentetic acid (Gd-DTPA)-loaded chitosan nanoparticles (Gd-nanoCPs) were prepared as MRI contrast agents. The MFH cells were cultured and collected into three falcon tubes that were set into the 3-tesra MRI system to acquire signal intensities from each pellet by the spin echo method, and the longitudinal relaxation time (T1) was calculated. The amount of Gd in the sample was measured by inductively coupled plasma atomic emission spectrography (ICP-AES). The accumulation of gadolinium in cells treated with Gd-nanoCPs was larger than that in cells treated with Gd-DTPA. In contrast, and compared with the control, Gd-DTPA was more effective than Gd-nanoCPs in reducing T1, suggesting that the larger accumulation exerted the adverse effect of lowering the enhancement of MRI. Further studies are warranted to gain insight into the therapeutic potential of Gd-NCT

36

Abstract 37

Title: Comparison of 3D Phase-Sensitive Inversion-Recovery and 2D Inversion-Recovery MRI at 3.0 T for the Assessment of Late Gadolinium Enhancement in Patients with Hypertrophic Cardiomyopathy

Authors: Kosuke Morita, RT, Daisuke Utsunomiya, MD, Seitaro Oda, MD, Masanori Komi, RT, Tomohiro Namimoto, MD, Toshinori Hirai, MD, Masahiro Hashida, RT, Seiji Takashio, MD, Megumi Yamamuro, MD, Yasuyuki Yamashita, MD

Source: Academic Radiology Volume 20, Issue 6, June 2013, Pages 752–757


Subjects:

Author Supplied Keywords: Magnetic resonance imaging; hypertrophic cardiomyopathy; late gadolinium enhancement; phase sensitive inversion recovery

Abstract: To compare free-breathing three-dimensional (3D) phase-sensitive inversion recovery (PSIR) with breath-holding two-dimensional (2D) IR sequences to determine which is better for detecting and characterizing myocardial late gadolinium enhancement (LGE) in hypertrophic cardiomyopathy (HCM) patients. Thirty HCM patients clinically underwent 3.0 T cardiac magnetic resonance imaging that included 3D-PSIR and 2D-IR. The amount of LGE lesions was calculated and expressed as %LGE of the myocardial mass, and the average of the %LGE value reported by two observers was recorded as the final %LGE. We also counted the number of LGE lesions and recorded their location. The myocardium-LGE contrast, margin sharpness, artifacts, and overall image quality were graded on a 4-point grading scale (1 = poor, 2 = fair, 3 = good, 4 = excellent). The mean %LGE on 2D-IR was 24.7 ± 0.6, 17.5 ± 0.6, and 8.5 ± 0.3, respectively, for the basal, mid-, and apical myocardium; the corresponding values were 24.2 ± 0.4, 20.0 ± 0.4, and 7.7 ± 0.3 on 3D-PSIR (2D-IR versus 3D-PSIR, P = .87). On 2D IR and 3D-PSIR images, 13, 52, and 53, and 9, 74, and 33 LGE lesions were detected in the subendocardial, midwall, subepicardial area, respectively. The myocardium-LGE contrast and overall image quality were significantly higher on 3D-PSIR than 2D-IR images (P < .001); the sequences did not differ significantly with respect to margin sharpness and artifact. Three-dimensional PSIR sequence yields higher image contrast, better image quality, and greater detection ability for LGE lesions than 2D-IR sequence.

37

Abstract 38

Title: Gadolinium(III) chelated conjugated polymer as a potential MRI contrast agent

Authors: Qingling Xu, Litao Zhu, Minghui Yu, Fude Feng, Lingling An, Chengfen Xing, Shu Wang

Source: Polymer Volume 51, Issue 6, 11 March 2010, Pages 1336–1340


Subjects:

Author Supplied Keywords: Conjugated polymers; Synthesis; MRI contrast agent

Abstract: Nuclear magnetic resonance imaging (MRI) has become a powerful technique in clinical diagnostics. In this work, a new MRI contrast agent by covalently linking Gd(III) chelates to the side chain of conjugated polymer (PF–Gd) is synthesized by Suzuki cross-coupling reaction. The PF–Gd exhibits a higher relaxivity and a pronounced enhancement in contrast than that of (NMG)2–Gd–DTPA widely used for clinical diagnosis. This work should be feasible to potentially lead to a new class of imaging contrast agents.

38

Abstract 39

Title: Gadolinium enhancement increases the sensitivity of MRI in detecting disease activity in multiple sclerosis

Authors: D. H. Miller, F. Barkhof, J. J. P. Nauta

Source: Brain A Journal of Neurology Volume 116, Issue 5, 1 October 1993


Subjects:


Abstract: There is now widespread agreement that serial brain MRI is useful in monitoring treatments designed to modify the course of multiple sclerosis. It has been less clear whether gadolinium enhancement is needed. We therefore compared the relative sensitivity of long repetition time (TR) spin echo (SE) and gadolinium enhanced short TR SE sequences in detecting active lesions. A blind analysis of the two sequences was performed in 26 untreated patients with early relapsing-remitting (19) or secondary progressive (seven) multiple sclerosis who underwent monthly MRI on four occasions (one baseline and three follow-up). Active lesions were defined as either new or enlarged lesions on long TR SE, or new or persistent enhancing lesions on short TR SE. In one patient there were 144 active lesions, all of which were seen with enhancement on short TR SE, but only 17 were seen on long TR SE. Amongst the remaining 25 cases, a total of 106 active lesions were seen: 68 (64%) were seen only with enhancement on short TR SE, 16 (15%) were seen only on long TR SE, while 22 (21%) were active on both sequences. We conclude that gadolinium enhancement markedly increases the sensitivity of monthly brain MRI in monitoring the treatment of relapsing-remitting or secondary progressive multiple sclerosis. With this frequency of scanning, a post contrast short TR SE sequence is the most sensitive method for detecting active lesions. The smaller yet still substantial incidence of active lesions seen only on the long TR SE sequence suggests that it should also be obtained.

39

Abstract 40

Title: Delayed gadolinium-enhanced MRI of cartilage (dGEMRIC) in early knee osteoarthritis

Authors: Carl Johan Tiderius, Lars E. Olsson, Peter Leander, Olle Ekberg and Leif Dahlberg

Source: Magnetic Resonance in Medicine Volume 49, Issue 3, pages 488–492, March 2003


Subjects:

Author Supplied Keywords: dGEMRIC;glycosaminoglycan;osteoarthritis;knee

Abstract: Delayed contrast-enhanced MRI of cartilage (dGEMRIC) is a noninvasive technique to study cartilage glycosaminoglycan (GAG) content in vivo. This study evaluates dGEMRIC in patients with preradiographic degenerative cartilage changes. Seventeen knees in 15 patients (age 35–70) with arthroscopically verified cartilage changes (softening and fibrillations) in the medial or lateral femoral compartment, knee pain, and normal weight-bearing radiography were included. MRI (1.5 T) was performed precontrast and at 1.5 and 3 hr after an intravenous injection of Gd-DTPA2− at 0.3 mmol/kg body weight. T1 measurements were made in regions of interest in medial and lateral femoral cartilage using sets of five turbo inversion recovery images. Precontrast, R1 (R1 = 1/T1, 1/s) was slightly lower in diseased compared to reference compartment, indicating increased hydration (P = 0.01). Postcontrast, R1 was higher in diseased than in reference compartment at 1.5 hr, 3.45 ± 0.90 and 2.64 ± 0.58 (mean ± SD), respectively (P < 0.01), as well as at 3 hr, 2.94 ± 0.60 and 2.50 ± 0.37, respectively (P = 0.01). The washout of the contrast medium was faster in diseased cartilage as shown by a higher R1 at 1.5 than at 3 hr in the diseased but not in the reference compartment. In conclusion, dGEMRIC can identify GAG loss in early stage cartilage disease with a higher sensitivity at 1.5 than 3 hr.

40

Abstract 41

Title: Meta-analysis of diagnosis of liver metastatic cancers: Comparison of 18FDG PET-CT and gadolinium-enhanced MRI

Authors: Jinlong Deng, Jiande Tang, and Naipeng Shen

Source: Journal of Medical Imaging and Radiation Oncology Volume 58, Issue 5, pages 532–537, October 2014


Subjects:

Author Supplied Keywords: liver metastasis; malignant tumor; MRI; PET-CT

Abstract: We performed a meta-analysis to compare the performance of 18F-fluorodeoxyglucose (18FDG) positron emission tomography-CT (PET-CT) with that of gadolinium-enhanced MRI for the detection of liver metastatic cancers. The MEDLINE and EMBASE databases were searched for relevant original articles. The histology and/or imaging follow-up data served as the reference standard. We calculated the pooled sensitivities, specificities, positive likelihood ratios, negative likelihood ratios and constructed summary receiver operating characteristic curves for 18FDG PET-CT and gadolinium-enhanced MRI, respectively. Ten studies (1105 patients) were included for this meta-analysis. 18FDG PET-CT has similar patient-based specificity (1.00 and 0.99), positive likelihood ratios (253.1 and 138.2), negative likelihood ratios (0.16 and 0.10) and area under curves (0.99 and 0.99) with gadolinium-enhanced MRI. Gadolinium-enhanced MRI tends to have higher sensitivity (0.91 and 0.84) than 18FDG PET-CT. Both 18FDG PET-CT and gadolinium-enhanced MRI have excellent diagnostic performance for the detection of liver metastatic cancer.

41

Abstract 42

Title: Gadolinium-based contrast agents for magnetic resonance cancer imaging

Authors: Zhuxian Zhou and Zheng-Rong Lu

Source: Nanomedicine and Nanobiotechnology Volume 5, Issue 1, pages 1–18, January/February 2013

Document Type:

Subjects:


Abstract: Magnetic resonance imaging (MRI) is a clinical imaging modality effective for anatomical and functional imaging of diseased soft tissues, including solid tumors. MRI contrast agents (CA) have been routinely used for detecting tumor at an early stage. Gadolinium-based CA are the most commonly used CA in clinical MRI. There have been significant efforts to design and develop novel Gd(III) CA with high relaxivity, low toxicity, and specific tumor binding. The relaxivity of the Gd(III) CA can be increased by proper chemical modification. The toxicity of Gd(III) CA can be reduced by increasing the agents' thermodynamic and kinetic stability, as well as optimizing their pharmacokinetic properties. The increasing knowledge in the field of cancer genomics and biology provides an opportunity for designing tumor-specific CA. Various new Gd(III) chelates have been designed and evaluated in animal models for more effective cancer MRI. This review outlines the design and development, physicochemical properties, and in vivo properties of several classes of Gd(III)-based MR CA tumor imaging.

42

Abstract 43

Title: T1 mapping of the gadolinium-enhanced myocardium: Adjustment for factors affecting interpatient comparison

Authors: Neville Gai, Evrim B. Turkbey, Saman Nazarian, Rob J. van der Geest, Chia-Ying Liu, João A. C. Lima, and David A. Bluemke

Source: Magnetic Resonance in Medicine Volume 65, Issue 5, pages 1407–1415, May 2011


Subjects:

Author Supplied Keywords: T1 mapping; myocardial fibrosis; patient T1 comparison; GFR; delayed enhancement

Abstract: Quantitative T1 mapping of delayed gadolinium-enhanced cardiac magnetic resonance imaging has shown promise in identifying diffuse myocardial fibrosis. Despite careful control of magnetic resonance imaging parameters, comparison of T1 times between different patients may be problematic because of patient specific factors such as gadolinium dose, differing glomerular filtration rates, and patient specific delay times. In this work, a model driven approach to account for variations between patients to allow for comparison of T1 data is provided. Kinetic model parameter values were derived from healthy volunteer time-contrast curves. Correction values for the factors described above were used to normalize T1 values to a matched state. Examples of pre- and post-corrected values for a pool of normal subjects and in a patient cohort of type 1 diabetic patients shows tighter clustering and improved discrimination of disease state.

43

Abstract 44

Title: Pretransplant diagnosis of hepatocellular carcinoma by gadoxetic acid–enhanced and diffusion-weighted magnetic resonance imaging

Authors: Jiyoung Hwang, Young Kon Kim, Jong Man Kim, Won Jae Lee, Dongil Choi and Seong Sook Hong

Source: Liver Transplantation Volume 20, Issue 12, pages 1436–1446, December 2014Document Type:

Subjects:

Author Supplied Keywords: liver; liver transplant; gadoxetic; MRI; acid

Abstract: We sought to evaluate the diagnostic performance of gadoxetic acid–enhanced magnetic resonance imaging (MRI) with and without additional diffusion-weighted imaging (DWI) in the detection of hepatocellular carcinoma (HCC) in pre-transplant patients. We included 63 liver transplant patients (54 men and 9 women; mean age = 52 years) who had undergone gadoxetic acid–enhanced MRI with DWI at 3.0 T within 90 days before transplantation. Two image sets were reviewed for HCC in 2 separate sessions by 2 independent observers: the gadoxetic acid set and the combined set (gadoxetic acid plus DWI). The sensitivity, specificity, positive predictive value, and negative predictive value were calculated for each image set. In all, 113 HCCs (size range = 0.5-7.8 cm, mean = 2.0 ± 1.3 cm) were identified in the 52 liver explants. The per-lesion sensitivity of the combined set (78.8% for both observers) was higher than the sensitivity of the gadoxetic acid set [71.7% (P = 0.02) and 72.6% (P = 0.03) for the 2 observers], with the highest trend for Child-Pugh class A (94.4% and 97.2% for gadoxetic acid and 97.2% for combined), which was followed by class B (73.2% for gadoxetic acid and 82.9% for combined) and then class C (47.2% for gadoxetic acid and 55.6% for combined, P = 0.01). The per-patient negative predictive value of the combined set was higher than that of the gadoxetic acid set for both observers (P = 0.046). There was no difference in specificity between the 2 image sets (P > 0.05). The addition of DWI to gadoxetic acid–enhanced MRI resulted in significantly higher sensitivity to detect HCC. However, the sensitivity decreased with increasing cirrhosis severity for both imaging types.

44

Abstract 45

Title: In vivo measurement of gadolinium diffusivity by dynamic contrast-enhanced MRI: A preclinical study of human xenografts

Authors: T. S. Koh, S. Hartono, C. H. Thng, T. K. H. Lim, L. Martarello5 and Q. S. Ng

Source: Magnetic Resonance in Medicine Volume 69, Issue 1, pages 269–276, January 2013


Subjects:

Author Supplied Keywords: dynamic contrast-enhanced MRI; tracer kinetics modeling; diffusion; Fick's law

Abstract: Compartmental tracer kinetic models currently used for analysis of dynamic contrast-enhanced MRI data yield poor fittings or parameter values that are un-physiological in necrotic regions of the tumor, as these models only describe microcirculation in perfused tissue. In this study, we explore the use of Fick's law of diffusion as an alternative method for analysis of dynamic contrast-enhanced MRI data in the necrotic regions. Xenografts of various human cancer cell lines were implanted in 14 mice that were subjected to dynamic contrast-enhanced MRI performed using a spoiled gradient recalled sequence. Tracer concentration was estimated using the variable flip angle technique. Poorly perfused and necrotic tumor regions exhibiting delayed and slow enhancement were identified using a k-means clustering algorithm. Tracer behavior in necrotic regions was shown to be consistent with Fick's diffusion equation and the in vivo gadolinium diffusivity was estimated to be 2.08 (±0.88) × 10−4 mm2/s. This study proposes the use of gadolinium diffusivity as an alternative parameter for quantifying tracer transport within necrotic tumor regions.

45

Abstract 46

Title: Pharmacokinetic and in vivo evaluation of a self-assembled gadolinium (III)-iron (II) contrast agent with high relaxivity

Authors: Tatjana N. Parac-Vogt, Luce Vander Elst, Kristof Kimpe, Sophie Laurent, Carmen Burtéa, Feng Chen, Rik Van Deun, Yicheng Ni, Robert N. Muller and Koen Binnemans

Source: Contrast Media & Molecular Imaging Volume 1, Issue 6, pages 267–278, November/December 2006


Subjects:

Author Supplied Keywords: magnetic resonance imaging; contrast agents; gadolinium; in vivo; pharmacokinetics; biodistribution; necrosis avidity

Abstract: A high-molecular weight tetrametallic supramolecular complex [(Ln-DTPA-phen)3Fe]− (Ln = Gd, Eu, La) has been obtained upon self-assembly around one iron(II) ion of three 1,10-phenantroline-based molecules substituted in 5 -position with the polyaminocarboxylate ′diethylenetriamine-N,N,N ,′ N ,′ N -pentaacetate, DTPA-phen′ 4−. The ICP-MS measurements indicated that the lanthanide:iron ratio is 3:1. Photoluminescence spectra of [Eu-DTPA-phen]− and of [(Eu-DTPA-phen)3Fe]− are nearly identical, implying that the first coordination sphere of the lanthanide(III) ion has not been changed upon coordination of phenantroline unit to iron(II) ion. NMRD measurements revealed that at 20 MHz and 310 K the relaxivity of the [(Gd-DTPA-phen)3Fe]− is equal to 9.5 ± 0.3 s−1 mM−1 of Gd (28.5 s−1 per millimole per liter of complex) which is significantly higher than that for Gd-DTPA (3.9 s−1 mM−1). The pharmacokinetic parameters of [(Gd-DTPA-phen)3Fe]− in rats indicate that the elimination of [(Gd-DTPA-phen)3Fe]− is significantly slower than that of Gd-DTPA and is correlated with a reduced volume of distribution. The low volume of distribution and the longer elimination time (Te1/2) suggest that the agent is confined to the blood compartment, so it could have an important potential as a blood pool contrast agent. The biodistribution profile of [(Gd-DTPA-phen)3Fe]− 2 h after injection indicates significantly higher concentrations of [(Gd-DTPA-phen)3Fe]− as compared with Gd-DTPA in kidney, liver, lungs, heart and spleen. The images obtained on rats by MR angiography show the enhancement of the abdominal blood vessels. The signal intensity reaches a maximum of 55% at 7 min post-contrast and remains around 25% after 90 min. MRI-histomorphological correlation studies of [Gd-DTPA-phen]− and [(Gd-DTPA-phen)3Fe]− showed that both agents displayed potent contrast enhancement in organs including the liver. The necrosis avidity tests indicated that, in contrast to the [Gd-DTPA-phen]− precursor complex, the supramolecular complex [(Gd-DTPA-phen)3Fe]− exhibits necrosis avidity.

46

Abstract 47

Title: Sensitivity of delayed gadolinium-enhanced MRI in multiple sclerosis

Authors: M. Filippi, T. Yousry, M. A. Rocca, G. Fesl, R. Voltz and G. Comi

Source: Acta Neurologica Scandinavica Volume 95, Issue 6, pages 331–334, June 1997


Subjects:

Author Supplied Keywords: multiple sclerosis; magnetic resonance imaging; gadolinium-DTPA; delayed scanning

Abstract: We performed this study to define the sensitivity of delayed gadolinium-enhanced magnetic resonance imaging (MRI) in detecting active lesions in the brains of patients with multiple sclerosis (MS). T1weighted images were obtained in 27 patients with relapsing-remitting or secondary progressive MS before, 5–7 min and 20–30 min after the injection of 0.1 mmol/kg gadolinium-DTPA. Results - One-hundred-and-three enhancing lesions were found on the early and 110 on the delayed scans (increase = 6.4%). Six patients had 8 additional lesions in the delayed scans, while 1 patient had 1 more lesion on the early scan. Two of the 12 (17%) patients with no enhancing lesions on the early scans had 2 enhancing lesions on the delayed scans. The average increase of enhancing lesion detection with delayed scanning was 14.5% for those patients who already had enhancing lesions on the early post-contrast scans. A significant increase of the enhancing lesion volume was found with delayed scanning (P=:0.004). These data indicate that it is possible to increase MRI sensitivity in detecting MS active lesions by delaying the scanning after gadolinium injection.

47

Abstract 48

Title: Liver MRI and histological correlates in chronic liver disease on multiphase gadolinium-enhanced 3D gradient echo imaging

Authors: Diego R. Martin MD, PhD, Thomas Lauenstein MD, Bobby Kalb MD, Christina Lurie MD, Hiroumi Kitajima PhD, Puneet Sharma PhD, Khalil Salman MD, Roger Moreira MD, Alton B. Farris III MD, James Spivey MD, Enrique Martinez MD, Steve Hanish MD, and Volkan Adsay MD

Source: Journal of Magnetic Resonance Imaging Volume 36, Issue 2, pages 422–429, August 2012


Subjects:

Author Supplied Keywords: liver fibrosis; hepatitis; chronic liver disease; chronic hepatitis; MRI; liver biopsy; histology

Abstract: To evaluate intrinsic hepatic enhancement patterns on multiphase, gadolinium-enhanced, fat-suppressed, 3D T1-weighted, gradient echo magnetic resonance imaging (MRI) as a quantitative correlate for severity of pathological changes in chronic liver disease (CLD). This study was HIPAA-compliant and Institutional Review Board-approved. In all, 75 patients were studied by contrast-enhanced multiphase abdominal MRI. CLD patients had liver histology correlation derived from right lobe liver biopsies. Contrast-enhanced arterial- and delayed-phase 3D gradient recalled echo (GRE) liver MRI were scored using feature categorization templates to quantify enhancement patterns by three independent readers. Liver histopathology was staged/graded for fibrosis/inflammation using the Scheuer system. Statistical testing for MRI histology correlates used a Pearson's product moment correlation and a Wilcoxon–Mann–Whitney two-sample rank-sum test. Reader agreement was analyzed by a modified Fleiss' kappa test. MRI histology correlation was high for delayed-phase MRI versus fibrosis stage (95% confidence interval [CI] 0.941 < r < 0.976, P = 5 × 10−7), but lower for all other comparisons (delayed-phase vs. inflammation and arterial-phase vs. inflammation or fibrosis all showed a CI no greater than 0.64). Paired testing between delayed-phase MRI score and histology fibrosis staging incremental levels was significant (from P < 10−2 to P < 10−5). A standard gadolinium-enhanced liver MRI may provide a correlate measure of hepatic fibrosis over a spectrum of severity.

48

Abstract 49

Title: Can unenhanced multiparametric MRI substitute gadolinium-enhanced MRI in the characterization of vertebral marrow infiltrative lesions?

Authors: Dalia Z. Zidan, Hesham A. Elghazaly

Source: The Egyptian Journal of Radiology and Nuclear Medicine Volume 45, Issue 2, June 2014, Pages 443–453


Subjects:

Author Supplied Keywords: Multi-parametric MRI; Gadolinium enhanced MRI; Diffusion weighted imaging; Apparent diffusion coefficient; Chemical shift imaging

Abstract: To assess the diagnostic effectiveness of unenhanced-multi-parametric magnetic resonance imaging (mp MRI) as an alternative to gadolinium (Gad)-enhanced MRI in the characterization of vertebral marrow infiltrative lesions. A prospective evaluation of fifty-six patients with suspected or untreated vertebral metastases undergoing MRI of the spine at 1.5 T was carried out. Two groups of sequences were assigned and compared for the characterization of marrow infiltrative lesions: group [A] unenhanced-mp MRI (including T1-weighted, T2-weighted, short time inversion recovery (STIR), diffusion weighted imaging (DWI) and in/opposed phase sequences) and group [B] gadolinium-enhanced MRI (including T1-weighted, T2-weighted, STIR and T1-weighted fat-suppressed gadolinium-enhanced sequence). Qualitative and quantitative image analysis was performed and compared. The sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV) and accuracy for both imaging techniques were calculated. There was no statistical significant difference between unenhanced-multi-parametric MRI and gadolinium-enhanced MRI as regards their diagnostic performance in differentiating benign from malignant vertebral marrow infiltrative lesions (p > 0.05) with calculated sensitivity (94% vs. 97%), specificity (92% vs. 88%), positive predictive value (94% vs. 91%), negative predictive value (92% vs. 95%) and (93% vs. 93%) accuracy. Unenhanced-multi-parametric MRI is compatible with gadolinium-enhanced MRI in reliable characterization of marrow infiltrative lesions. The routine MRI protocol of cancer patients should be altered to accommodate the evolving MRI technology and cost effectively substitute the need for a gadolinium enhanced scan.

49

Abstract 50

Title: Association between delayed gadolinium-enhanced MRI of cartilage (dGEMRIC) and joint space narrowing and osteophytes

Authors: H. Owman, Y.B. Ericsson, M. Englund, C.J. Tiderius, J. Tjörnstrand, E.M. Roos‖, L.E. Dahlberg

Source: Osteoarthritis and Cartilage Volume 22, Issue 10, October 2014, Pages 1537–1541


Subjects:

Author Supplied Keywords: dGEMRIC; Osteoarthritis; Glycosaminoglycans; Cartilage; Knee

Abstract: To examine the association between the relaxation time (T1Gd) of delayed gadolinium-enhanced magnetic resonance imaging of cartilage (dGEMRIC) and grade of tibiofemoral joint space narrowing (JSN) and osteophytosis 11 years later, in a cohort of meniscectomized patients. Patients (n = 45) aged 35–50 who had undergone an arthroscopic partial medial meniscectomy 1–6 years earlier, due to degenerative meniscal tear, were examined using dGEMRIC. These patients had no cartilage changes defined as deep clefts or visible bone at the time of arthroscopy. Eleven years later (12–16 years after surgery) 34 of these subjects (76%) were evaluated by weight-bearing knee radiography, and tibiofemoral joint changes were graded according to the Osteoarthritis Research Society International Atlas. Lower T1Gd in the medial compartment was associated with higher grade of medial JSN (grade 0, 351 ms; grade 1, 386 ms; grade 2, 342 ms; grade 3, 259 ms [P for trend < 0.001]) and more osteophytosis (score 0, 371 ms; score 1, 389 ms; score 2, 354 ms; score 3, 289 ms; score 4, 265 ms; score 5, 275 ms [P for trend = 0.001]). Lower T1Gd in the lateral compartment was associated with higher grade of lateral JSN (grade 0, 436 ms; grade 1, 346 ms [P for trend = 0.026]). The current study suggests that lower T1Gd measured with dGEMRIC of medial and lateral femoral cartilage is associated with higher grade of JSN 11 years later, and medially, also with more osteophytosis.

50

Abstract 51

Title: Histological validation of iron-oxide and gadolinium based MRI contrast agents in experimental atherosclerosis

Authors: Brigit den Adel, Sandra M. Bovens, Bernard te Boekhorst, Gustav J. Strijkers, Robert E. Poelmann, Louise van der Weerd, Gerard Pasterkamp

Source: Atherosclerosis Volume 225, Issue 2, December 2012, Pages 274–280


Subjects:

Author Supplied Keywords: MRI; Contrast agent; Atherosclerosis; Histology

Abstract: MRI using targeted contrast agents (CA) has emerged as a promising technique to study atherothrombotic disease in vivo. Particularly, the use of targeted Gd and lipid-based nanoparticles has enabled detailedin vivo imaging of various molecular markers of atherosclerotic plaque pathophysiology. For validation purposes, it is crucial that nanoparticle accumulation in the plaque, cellular association and localization can be assessed by ex vivo immuno-histology or fluorescence microscopy of tissue sections. In this review we discuss the various methods that are available for histological evaluation of targeted MRI contrast agents such as lipid-based nanoparticles and iron oxide particles. We discuss the detection of these contrast agents in paraffin-embedded and in cryopreserved tissue sections of atherosclerotic plaques. During the embedding procedure in paraffin, most components of targeted lipid-based nanoparticles are generally washed out, though the actual targeting moieties may be retained in the embedded sections. Therefore staining of the antibody–antigen complex provides a suitable way to visualize the presence of the nanoparticle in the plaque. In cryosections, the localization of nanoparticles can be assessed directly by measuring the fluorescence of an incorporated fluorophore or by secondary stainings of the Gd-containing DTPA lipids or the iron oxide particles. With certain secondary stainings, be it for the contrast agent or for co-localization with the target, the contrast agent itself may interfere with standard histological protocols, yielding false positive results. The here presented techniques enable proper visualization of MR contrast agent accumulation and localization in atherosclerotic plaque, which will provide the validation necessary to advance these lipid-based nanoparticles to the clinic.

51

Abstract 52

Title: Optimal Techniques for Late Gadolinium-Enhanced MRI: Comparison of Delay Time, Slice Thickness, and Multiplanar Reconstruction vs Maximum Intensity Projection for Assessment of Fibrosis in Atrial Fibrillation

Authors: I.M. Khurram, R. Beinart, V. Zipunnikov, H. Calkins, S.L. Nazarian, S. Zimmerman

Source: Heart Rhythm Volume 10, Issue 11, November 2013, Pages 1751


Subjects:


Abstract: Left atrial (LA) late gadolinium enhancement (LGE) magnetic resonance imaging (MRI) has varying protocols, which may limit interstudy comparisons. This study evaluates whether changes in image acquisition and reconstruction parameters affect quantification of LA LGE MRI. A total of 200 LGE MRI scans were prepared using various techniques from 5 subjects. 3D respiratory and ECG-gated LGE images were acquired at 15, 20, 25, and 30 minutes after contrast. Multiplanar reconstructions (MPR) and maximum intensity projections (MIP) were created from 3D data at various slice thicknesses. LA LGE was quantified with image intensity ratio (IIR, atrial wall signal intensity divided by blood pool). Mean IIR was calculated for the entire LA as a metric of LGE burden. Additionally, in 42 consecutive preablation patients, local IIR values from 3.5-mm MPR and MIP reconstructions were separately registered to LA electroanatomic voltage maps (EAM) obtained prior to ablation procedure. Multitime point LGE-MRI showed a rise in baseline mean IIR of 0.5% ± 0.1% per minute (P <.001) in MPR and a rise of 0.6% ± 0.1% (P <.001) for MIP using regression analysis (Figure A). The MPR- and MIP-based mean IIRs diverged, showing change of –0.3% for MPR and +1.1% for MIP for 1-mm increase in slice thickness (P <.001 for both; Figure B). A total of 4428 EAM points were registered to local LA wall IIRs from both MPR and MIP techniques. An increase of a single unit of IIR was related to drop in 1.20 mV with MPR and 1.25 mV with MIP (P <.001 for both). Variations in timing of acquisition, image reconstruction methods, and slice thickness result in changes in LA LGE quantity.

52

Abstract 53

Title: Subcellular SIMS imaging of gadolinium isotopes in human glioblastoma cells treated with a gadolinium containing MRI agent

Authors: Duane R. Smith, Daniel R. Lorey II, Subhash Chandra

Source: Applied Surface Science Volumes 231–232, 15 June 2004, Pages 457–461


Subjects:

Author Supplied Keywords: SIMS ion microscopy; BNCT; Gadolinium; Gd-DTPA; GdNCT; T98G human glioblastoma cells

Abstract: Neutron capture therapy is an experimental binary radiotherapeutic modality for the treatment of brain tumors such as glioblastoma multiforme. Recently, neutron capture therapy with gadolinium-157 has gained attention, and techniques for studying the subcellular distribution of gadolinium-157 are needed. In this preliminary study, we have been able to image the subcellular distribution of gadolinium-157, as well as the other six naturally abundant isotopes of gadolinium, with SIMS ion microscopy. T98G human glioblastoma cells were treated for 24 h with 25 mg/ml of the metal ion complex diethylenetriaminepentaacetic acid Gd(III) dihydrogen salt hydrate (Gd-DTPA). Gd-DTPA is a contrast enhancing agent used for MRI of brain tumors, blood–brain barrier impairment, diseases of the central nervous system, etc. A highly heterogeneous subcellular distribution was observed for gadolinium-157. The nuclei in each cell were distinctly lower in gadolinium-157 than in the cytoplasm. Even within the cytoplasm the gadolinium-157 was heterogeneously distributed. The other six naturally abundant isotopes of gadolinium were imaged from the same cells and exhibited a subcellular distribution consistent with that observed for gadolinium-157. These observations indicate that SIMS ion microscopy may be a viable approach for subcellular studies of gadolinium containing neutron capture therapy drugs and may even play a major role in the development and validation of new gadolinium contrast enhancing agents for diagnostic MRI applications.

53

Abstract 54

Title: Early-enhancing Non-neoplastic Lesions on Gadolinium-enhanced MRI of the Liver

Authors: M Kanematsu, H Kondo, R.C Semelka, M Matsuo, S Goshima, H Hoshi, N Moriyama, Y Itai



Subjects: liver; MR imaging; contrast enhancement; cirrhosis; angiography; arterioportal shunts; pseudolesion


Abstract: To assess the frequency, cause, and significance of early-enhancing, non-neoplastic (EN) lesions on gadolinium-enhanced magnetic resonance imaging (MRI) of the liver performed for the detection of malignant hepatic tumors. From September 1997 to September 2000, we reviewed the images of 125 patients, suspected of having hepatic tumors, in whom (1) gadolinium-enhanced triphasic dynamic gradient-recalled-echo (GRE) imaging in addition to unenhanced T1- and T2-weighted MRI was performed, (2) conventional angiography and combination computed tomography (CT) hepatic arteriography and CT during arterial portography were performed within 2 weeks of the MRI, and (3) definitive surgery within 2 weeks of the MRI or follow-up study by means of intravenously contrast-enhanced CT or MRI in 10 months or more was performed. Angiographic studies were correlated to determine the underlying causes of the EN lesions. We found 78 EN lesions in 36 patients (29%), ranging in size from 4 and 50 mm (mean, 12.2 mm). From the MR reports, our radiologists had prospectively diagnosed EN lesions as probable malignant tumors in eight (10%), possible malignant tumors in 36 (46%), and probable non-neoplastic lesion in 34 (44%). EN lesions were found in 27 of 81 (33%) cirrhotic patients and in nine of 44 (20%) non-cirrhotic patients. Fifty-one EN lesions (65%) were located along the liver edge. The shape was circular in 42 (54%), oval in 14 (18%), irregular in 12 (15%), wedge-shaped in seven (9%), and fan-shaped in three (4%). Twenty EN lesions (26%) appeared slightly hyper intense on T2-weighted images. The causes were non-neoplastic arterio-portal shunting in 48 (62%), cystic venous drainage in four (5%), rib compression in four (5%), aberrant right gastric venous drainage in two (3%), and unknown in 20 (26%). Over half the number of EN lesions were caused by non-neoplastic arterio-portal shunting, occasionally showing slight hyper intensity on T2-weighted images. On MR images the non-neoplastic nature of the EN lesion was often ascertained. Radiologists should not overcall EN lesions as malignant as the patients involved would be inappropriately considered inoperable. In problematic cases, further investigation with angiographic CT or follow-up imaging studies should be performed.

54

Abstract 55

Title: Cobalt (Co) as a PET-tracer in stroke, compared with blood flow, oxygen metabolism, blood volume and gadolinium-MRI

Authors: Henk Stevensa, f, Hugo M.L Jansena, Jacques De Reucka, b, Marc Lemmerlingc, Karel Strijckmansd, Patrick Goethalsd, Ignace Lemahieue, Bauke M de Jongg, Antoon T.M Willemsenh, Jakob Korf

Source: Journal of the Neurological Sciences Volume 171, Issue 1, 1 December 1999, Pages 11–18


Subjects:

Author Supplied Keywords: Cerebral ischemia; Cobalt; Cerebral blood flow; Cerebral oxygen metabolic rate; Tomography; Emission-computed

Abstract: Several studies have shown the feasibility of divalent cobalt (Co)-isotopes (55Co and 57Co) in imaging of neuronal damage in stroke, multiple sclerosis, cerebral tumors and traumatic brain injury. Little is known how regional Co uptake relates to other pathophysiological changes after stroke. Therefore, we compared55Co-PET with functional parameters such as regional cerebral blood flow (rCBF) using C15O2, regional oxygen metabolism (rCMRO2) using 15O2, regional cerebral blood volume (rCBV) and post-gadolinium (Gd) T1w-MRI to assess the permeability of the blood–brain-barrier (BBB). Sixteen patients (10 female; six male) aged 43 to 84 (mean 69) years with first ever stroke, as shown by CT or MRI, were examined with55Co-PET and C15O2-, 15O2- and C15O-PET in one single session, in a period varying from 0 to 30 days after stroke-onset. Regions of infarction on C15O2- and 15O2-PET (defined by rCMRO2<65% or rCBF<45% of the contralateral value) were subsequently superimposed on the 55Co-PET scan. Clinical status was established using the Orgogozo stroke scale, which was assessed both at day 1 and at discharge (at least 6 weeks after day 1). Accumulation of 55Co was seen in eight out of 16 patients, occurring in areas showing a diminished oxygen metabolism, was only partially related to blood flow, and was located mainly outside the extent of the infarction or luxury perfusion as seen on post-Gd T1w-MRI. Statistical analysis showed a negative correlation between the Orgogozo score at discharge and the uptake of radioactive cobalt.

55

Abstract 56

Title: MRI gadolinium-based contrast agents.

Authors: J.-P. Goulléa, A. Cattanéoc, E. Saussereaua, L. Mahieua, M. Guerbetb, C. Lacroix

Source: Annales Pharmaceutiques Françaises Volume 67, Issue 5, September 2009, Pages 335–339


Subjects:

Author Supplied Keywords: Gadolinium; Nephrogenic systemic fibrosis

Abstract: Gadolinium (Gd) is used in contrast agents as it enhances magnetic resonance imaging (MRI) signals. To reduce Gd toxicity, it is chelated into linear or macrocyclic complexes. Eight Gd-containing contrast agents have been approved by the European Medicines Agency (EMEA) for use in MRI, and six by the US Food and Drug Administration. Stability depends upon its physicochemical properties. When renal function is normal, the Gd is quickly cleared from the body by the kidneys. For patients with chronic kidney disease, the elimination is greatly reduced and Gd may be released from its chelate and deposit in body tissues, leading to nephrogenic systemic fibrosis (NSF). More than 200 cases of NSF have been reported in the world. NSF is characterized by an extensive fibrosis of skin and tissues, a very severe affection with possible lethal outcome. We propose recommendations to avoid the risk of NSF.

56

Abstract 57

Title: High-intensity signals in the basal ganglia from gadolinium-enhanced T1-weighted MRI as an early change in toxoplasma encephalitis in an AIDS patient

Authors: Kei Suzuki, Masahiro Masuya, , Takeshi Matsumoto, Naomi Ito, Kohshi Ohishi, Naoyuki Katayama, Masayuki Maeda

Source: Journal of Infection and Chemotherapy Volume 16, Issue 2, 2010, Pages 135–138


Subjects:

Author Supplied Keywords: Toxoplasma; Encephalitis; Magnetic resonance imaging (MRI); AIDS

Abstract: A 30-year-old Brazilian man hospitalized with AIDS developed a high-grade fever. Neither culture studies nor radiological examinations revealed the cause; small yet highly intense signals in the basal ganglia were detected upon gadolinium (Gd)-enhanced T1-weighted magnetic resonance imaging (MRI) of the head. This finding was equivocal at that time but obviously abnormal for his age. A week later, he developed a movement disorder in his right arm, speech apraxia, and a worsening disturbance of consciousness. Repeated Gd-enhanced T1-weighted MRI demonstrated incredible changes in the brain; enhanced lesions in the basal ganglia deteriorated over time, multiple nodular and ring-enhanced lesions were observed in almost the entire brain. A diagnosis of toxoplasma encephalitis (TE) was confirmed by the detection of Toxoplasma gondii DNA in the cerebrospinal fluid. After initiation of intravenous trimethoprim-sulfamethoxazole (TMP-SMX; 10 mg/kg/day of TMP and 50 mg/kg/day of SMX) treatment, his symptoms and radiological findings improved dramatically. Our case suggests that high-intensity signals seen in the basal ganglia of a Gd-enhanced T1-weighted MRI, even at the preclinical stage, is indicative of TE. Because the use of MRI in general has become more widespread, it is predicted that preclinical lesions of TE will be found in various clinical settings more frequently.

57

Abstract 58

Title: Small molecular gadolinium (III) complexes as MRI contrast agents for diagnostic imaging

Authors: Kannie Wai-Yan Chan, Wing-Tak Wong

Source: Coordination Chemistry Reviews Volume 251, Issues 17–20, September 2007, Pages 2428–2451


Subjects:

Author Supplied Keywords: MRI contrast agents; Gadolinium (III) complexes; Molecular imaging; Protein probes; Polyaminocarboxylates

Abstract: Magnetic resonance imaging (MRI) contrast agents that contain the gadolinium ion are widely used in biomedical research and diagnosis. The relaxation mechanism of these T1-agents highlights their sensitivity towards the proximal environment. Greater knowledge of the structurally related relaxation mechanism, particularly factors that govern relaxivity, leads to scrutinized chelate designs that improve contrast enhancement. Cyclic and acyclic polyaminocarboxylate gadolinium complexes, especially those have favorable water exchange and tumbling rate for relaxation, have been reported to improve relaxivity and specificity. The criteria for a large relaxivity gain upon protein binding, such as the human serum albumin (HSA), are elucidated through the relaxometric study of the protein–chelate adduct. This adduct is an important model for the development of contrast agents, which may allow the in vivo visualization of proteins. The strength of HSA binding and the observed relaxivity are related to the pharmacokinetic profile of the contrast agents and give insight in the sensitivity of the agents after intravenous administration. By using animal models, an understanding of the physiology of contrast agents, including their bio distribution, excretion, and possible site of interaction, is acquired. The in vitro studies of contrast agents have demonstrated the feasibility of imaging various disease-related proteins, cell types, and gene delivery and expression. Imaging at the molecular level can be achieved through this integrative approach and the incorporation of nanotechnology in drug delivery.

58

Abstract 59

Title: Comparison of diffuse hepatocellular carcinoma and intrahepatic cholangiocarcinoma using sequentially acquired gadolinium-enhanced and Resovist-enhanced MRI

Authors: Young Kon Kim, Young Min Han, Chong Soo Kim

Source: European Journal of Radiology Volume 70, Issue 1, April 2009, Pages 94–100


Subjects:

Author Supplied Keywords: Liver neoplasm; Magnetic resonance imaging; Hepatocellular carcinoma; Bile duct; Neoplasm

Abstract: The purpose of this study was to compare MRI findings of diffuse hepatocellular carcinoma (D-HCC) and intrahepatic cholangiocarcinoma (IHC) to identify characteristics of each. We retrospectively analyzed MRI that consisted of unenhanced T1- and T2-weighted image, gadolinium (Gd)-enhanced dynamic image, and sequentially acquired Resovist-enhanced image from 29 patients with D-HCCs and 32 patients with IHC. On T2-weighted imaging, D-HCCs usually appeared as poorly defined, infiltrative mildly hyperintense masses, whereas IHC appeared as well-defined, lobulated mildly hyperintense masses with areas of strong hyperintensity and hypointensity. On dynamic- and Resovist-enhanced T1-weighted MRIs, D-HCCs appeared as hypovascular and homogeneously hypointense or isointense masses with internal reticulation, whereas IHD appeared as centripetal enhancing masses with or without delayed central hyperintensity. Biliary dilatation was predominantly observed in the area adjacent to the IHC and in the intratumoral area of D-HCC. Portal venous tumor thrombus was observed in most of the D-HCC, and portal vein encasement was seen in 17 of the IHC. D-HCC and IHC exhibited characteristics of each at T1- and T2-weighted imaging, Gd-enhanced dynamic imaging, and sequentially acquired Resovist-enhanced T1-weighted imaging.

59

Abstract 60

Title: The gadolinium complexes with polyoxometalates as potential MRI contrast agents

Authors: Zhongfeng Lia, Weisheng Li, Xiaojing Lia, Fengkui Peia, Yingxia Lib, Hao Leic

Source: Magnetic Resonance Imaging Volume 25, Issue 3, April 2007, Pages 412–417


Subjects:

Author Supplied Keywords: Magnetic resonance imaging (MRI); Contrast agent; Gadolinium polyoxometalates; Relaxivity

Abstract: The two gadolinium (Gd) polyoxometalates, K15[Gd(BW11O39)2] [Gd(BW11)2] and K17[Gd(CuW11O39)2] [Gd(CuW11)2] have been evaluated by in vivo and in vitro experiments as the candidates of potential tissue-specific magnetic resonance imaging (MRI) contrast agents. T1 relaxivities of 17.12 mM−1·s−1 for Gd(BW11)2 and 19.95 mM−1·s−1 for Gd(CuW11)2 (400 MHz, 25 °C) were much higher than that of the commercial MRI contrast agent (GdDTPA). Their relaxivities in bovine serum albumin and human serum transferrin solutions were also reported. After administration of Gd(BW11)2 and Gd(CuW11)2 to Wistar rats, MRI showed longer and remarkable enhancement in rat liver and favorable renal excretion capability. The signal intensity increased by 37.63±3.45% for the liver during the whole imaging period (100 min) and by 61.47±10.03% for kidney within 5–40 min after injection at 40±1-μmol·kg−1 dose for Gd(CuW11)2, and Gd(BW11)2 induced 50.44±3.51% enhancement in the liver in 5–50-min range and 61.47±10.03% enhancement for kidney within 5–40 min after injection at 39±4 μmol·kg−1 dose. In vitro and in vivo study showed that Gd(BW11)2 and Gd(CuW11)2 are favorable candidates as tissue-specific contrast agents for MRI.

60

Abstract 61

Title: Pancreatic hemangioma: Imaging features with contrast-enhanced CT and with gadolinium- and mangafodipir-enhanced MRI

Authors: Christina Planka, Bruno Niederleb, Ahmed Ba-Ssalamaha, Wolfgang Schima

Source: European Journal of Radiology Extra Volume 57, Issue 2, February 2006, Pages 59–62


Subjects:

Author Supplied Keywords: CT; MRI; Gadolinium; Mangafodipir; Pancreas; Hemangioma

Abstract: Pancreatic hemangioma is an extremely rare tumor, with only a very few cases reported in the literature. We present the case of a 36-year-old man admitted to the hospital with jaundice and abdominal pain. Contrast-enhanced CT showed a hypervascular mass with large vessels in the pancreatic head. The mass appeared moderately hypervascular on gadolinium-enhanced MRI, and, on mangafodipir-enhanced MRI, no contrast agent uptake into the mass could be detected. Despite the size of the lesion, no dilatation of the pancreatic and the common bile duct were seen. Pancreatic hemangioma should be included in the list of differential diagnoses in case of a hypervascular pancreatic lesion without signs of mass effect.

61

Abstract 62

Title: Synthesis of a tricyclic tetraazatriacetic ligand for gadolinium(III) as potential contrast agent for MR

Authors: Fabienne Diourya, Sophie Samboua, Emmanuelle Guénéa, Monique Sabatoub, Clotilde Ferrouda, Alain Guya, Marc Portb

Source: Tetrahedron Volume 63, Issue 1, 1 January 2007, Pages 204–214


Subjects:

Author Supplied Keywords: Contrast agent for MRI; Gadolinium complex; PCTA12 derivative; Macrocyclic polyaza-polycarboxylic acid

Abstract: A tricyclic tetraazatriacetic compound, which is a rigidified derivative of PCTA12 ligand with a cyclohexylene bridge replacing an ethylene one, was prepared. Two synthetic routes have been investigated, both of them implying a common functionalized triamine intermediate. Whatever the route, four synthetic steps were necessary to obtain the target tricyclic ligand. The more effective one (Route B) led to the desired compound in 19% overall yield from the triamine intermediate. The corresponding gadolinium complex of 1/1 stoichiometry was then prepared in order to evaluate it as potential contrast agent for MRI.

62

Abstract 63

Title: MRI of liver tumors using gadolinium-DOTA: Prospective study comparing spin-echo long TR-TE sequence and CT

Authors: Charles A. Cuenod∗, Marie F. Bellin, Jean C. Bousquet∗, André Duron∗, Eric Auberton∗, Bernard M. Mazoyer†, Daniel Khayat‡, Pierre Opolon§, Jacques Grellet∗Source: Magnetic Resonance Imaging Volume 9, Issue 2, 1991, Pages 235–245


Subjects:

Author Supplied Keywords: Gadolinium-DOTA; MRI; Liver tumor

Abstract: Thirty-nine patients with liver tumors were examined using MRI at 0.5 T before and after intravenous bolus injection of either 0.1 mmol/kg (n = 18) or 0.2 mmol/kg (n = 21) of Gadolinium-Dota, using spin-echo T1- and T2-weighted sequences before injections and spin-

echo or gradient-echo sequences after injection. When contrastto-noise ( ) data were

normalized relative to time, optimal mean was observed after gadolinium injection.

However, subjective study and case-by-case measurement showed better contrast for SE 2000/60 and CT with injection in 62% and 42% of cases, respectively.

63

Abstract 64

Title: Gadolinium-DTPA-enhanced MRI of intraocular tumors

Authors: Gerhard Adam, Matthias Brab, Klaus Bohndorfa, Rolf W. Günthera



Subjects:

Author Supplied Keywords: Gadolinium-DTPA; MRI, uveal melanoma

Abstract: The value of gadolinium-enhanced MRI in 30 patients with intraocular lesions has been evaluated. Seventeen patients had a uveal melanoma, two a ciliary body melanoma, three had uveal metastases, one lymphoma, four had senile macula degenerations, and three uveal nevi. Twelve of 17 patients with melanoma were followed up by MRI after ruthenium plaque therapy on 2–4 occasions. Melanomas showed high precontrast signal intensities and only a slight enhancement after intravenous Gd-DTPA was given. After ruthenium plaque therapy precontrast signal intensities (SI) decreased while a moderate signal increase on postcontrast scans was noted. Scars or tumor residues were better delineated on enhanced images. All other tumors than melanotic melanomas showed low SI on precontrast scans and a high signal increase after Gd-DTPA administration. Small amelanotic tumors were better delineated on postcontrast scans. In addition Gd-DTPA-enhanced MRI allowed differentiation between tumor and hemorrhage. No signal increase after Gd-DTPA application was seen in subretinal or vitreous hemorrhages of varying ages.

64

Abstract 65

Title: Value of Gadolinium in Brain MRI Examinations for Developmental Delay

Authors: Bradley R. Foerster, MD⁎, Jamal Ksar, MD⁎, Myria Petrou, MD⁎, Petr O. Eldevik, MD⁎, Pavel V. Maly, MD†, Martha D. Carlson, MD, PhD‡, Pia C. Sundgren, MD, PhD

Source: Pediatric Neurology Volume 35, Issue 2, August 2006, Pages 126–130


Subjects:


Abstract: The aim of this study was to evaluate the added utility of gadolinium administration in the magnetic resonance imaging evaluation of developmental delay in children less than 2 years of age. A computerized retrospective study identified all brain magnetic resonance imaging examinations using gadolinium performed at our institution from 1995–2002 for children under the age of 2 years. Review of the clinical records and magnetic resonance imaging reports identified 170 brain magnetic resonance imaging examinations that were performed for developmental delay. Magnetic resonance imaging studies with enhancing lesions were reviewed by two staff neuroradiologists and two radiology residents. Contrast administration was rated as essential, helpful, or not helpful for each study. In the 107 patients in whom developmental delay was the primary concern, there were no cases in which the findings would have been missed without gadolinium administration. In the 63 patients in whom developmental delay was a secondary concern, there were several cases (11%) where contrast was helpful but not essential in reaching a radiologic diagnosis. In conclusion, intravenous gadolinium has an extremely low yield in children under the age of 2 where developmental delay is the primary concern. In young children for whom developmental delay is a secondary concern, we advocate the use of gadolinium particularly where tumor or infection is clinically suspected

65

Abstract 66

Title: Hepatocellular carcinoma: Conventional MRI findings including gadolinium-enhanced dynamic imaging

Author: Katsuyoshi Ito

Source: European Journal of Radiology Volume 58, Issue 2, May 2006, Pages 186–199


Subjects:

Author Supplied Keywords: Hepatocellular carcinoma (HCC); Chemical shift imaging; Advanced HCC; Early HCC; Dysplastic nodule; Multi-arterial-phase dynamic MR imaging

Abstract: A great variety of MR pulse sequences for hepatocellular carcinomas (HCCs) are now available. In this article, we reviewed the current MR imaging techniques that are routinely used for hepatic imaging, and described the optimization of these sequences as well as the utility and characteristics of each sequence for the accurate diagnosis of HCCs. Then, we reviewed various MR imaging findings of advanced and early HCCs with emphasis on signal intensity and hemodynamic patterns. Finally, we described the value of multi-arterial-phase contrast-enhanced dynamic MR imaging of the whole liver with excellent temporal resolution for evaluating transitional hemodynamics of hepatic lesions during the six arterial phases.

66

Abstract 67

Title: Age-related gadolinium-enhancement of MRI brain lesions in multiple sclerosis

Authors: Carla Tortorellaa, Alessandra Bellacosab, Damiano Paolicellib, Aurora Fuianib, Elisabetta Di Monteb, Isabella Laura Simoneb, Patrizia Giaquintob, Paolo Livreab, Maria Trojano

Source: Journal of the Neurological Sciences Volume 239, Issue 1, 15 December 2005, Pages 95–9


Subjects:

Author Supplied Keywords: Multiple sclerosis; Age; Gd enhancement

Abstract: There is evidence that inflammatory processes in multiple sclerosis (MS) are age-dependent. In this study we evaluated the impact of aging on gadolinium (Gd) enhancement of brain magnetic resonance imaging (MRI) lesions in MS patients. Pre- and post-contrast MRI scans, acquired using a standardized procedure by the same MRI scanner, at least 1 month far from clinical relapse or steroid treatment, were examined in 200 disease-modifying treatment free MS patients. Seventy-three patients (36.5%) showed at least one enhancing lesion. Age at MRI examination (p = 0.0001), disease duration (p = 0.002) and EDSS score were significantly (p = 0.02) lower, whereas relapse rate in the preceding 2 years was higher (p = 0.003) in patients with enhancing lesions than in patients with unenhancing scans. Multivariate logistic analysis showed that current age was the variable better predicting Gd enhancement (p = 0.004). The odds ratios were 0.95 (CI: 0.92–0.98) for each year of patient's age and 0.64 (CI: 0.48–0.87) for each age decade. The main changes in enhancement risk occurred after 35 years of age. Multivariate Poisson regression model showed that relapse rate in the preceding 2 years (p < 0.0001) and current age (p = 0.0003) were the best predictors of the number of enhancing lesions. This information can be used to increase the statistical power of clinical trials using Gd-enhancing lesions as an outcome measure.

67

Abstract 68

Title: Decreased levels of CD95 and caspase-8 mRNA in multiple sclerosis patients with gadolinium-enhancing lesions on MRI

Authors: Andreia C. Gomesa, Michael Morrisb, c, Leszek Stawiarza, Gun Jönssond, Prabhakar Puthetie, Lena Bronge, Hans Linke, Jan Hillerta

Source: Neuroscience Letters Volume 352, Issue 2, 4 December 2003, Pages 101–104


Subjects:

Author Supplied Keywords: Multiple sclerosis; Magnetic resonance imaging; Apoptosis; CD95; Caspase-8; Gadolinium-enhancing lesions

Abstract: Magnetic resonance imaging (MRI) allows examining inflammation and central nervous system (CNS) tissue damage in patients suffering from multiple sclerosis (MS), a demyelinating disease of the CNS. Using real-time PCR, we quantified mRNA levels of apoptosis regulators CD95, CD95 ligand, caspase-8, -10 and cellular FLICE-inhibitory protein (cFLIP), and cytokines IL-10 and TNF-α in blood mononuclear cells of MS patients at the time of MRI examination. Patients with detectable gadolinium-enhancing lesions had lower expression of CD95 and caspase-8 (P<0.05). Lesion load and brain atrophy did not correlate with expression levels of any of the target molecules studied. Disease duration correlated positively with both FLIP/caspase-8 and CD95/CD3 ratios (P<0.05). These results support the notion that the CD95-dependent pathway plays a complex role in the regulation of survival of activated immune cells in MS

68

Abstract 69

Title: Gadolinium-enhanced dynamic MRI of breast hemangioma

Authors: Kazumasa Hayasaka, Yoshiaki Tanaka, Tomoya Saitoh, Motoichiroh Takahashi

Source: Computerized Medical Imaging and Graphics Volume 27, Issue 6, November–December 2003, Pages 493–4


Subjects:

Author Supplied Keywords: Hemangioma; Breast; Magnetic resonance imaging; Gadolinium enhanced dynamic study

Abstract: We describe a patient with hemangioma of the breast. The tumor showed an Ill-defined hypo-intense mass on T1-weighted imaging and hyper-intense mass on T2-weighted imaging. After bolus gadolinium injection, the tumor showed heterogeneous enhancement in early phase and in the time-intensity an early intensive enhancement was followed by a plateau. This intensive enhancement in the early phase is not limited to breast carcinoma but can be found in breast hemangiomas as well.

69

Abstract 70

Title: An evaluation of gadolinium polyoxometalates as possible MRI contrast agent

Authors: Jianghua Fenga, Xiaojing Lia, Fengkui Pei, Guoying Suna, Xu Zhangb, Maili Liu



Subjects:

Author Supplied Keywords: Gadolinium polyoxometalates; Relaxivity; MRI; Contrast agent

Abstract: Two gadolinium polyoxometalates, K9GdW10O36 and K11[Gd(PW11O39)2], have been evaluated both in vivo and in vitro as candidates for tissue-specific MRI contrast agents. T1-relaxivities of 6.89 mM−1 · s−1 for K9GdW10O36 and 5.27 mM−1 · s−1 for K11[Gd(PW11O39)2] are slightly higher than that of the commercial MRI contrast agent (Gd-DTPA). Both compounds bind with bovine serum albumin and human serum transferrin and favorable liver-specific contrast enhancement in in vivo MRI with Sprague-Dawley rats after i.v. administration has been demonstrated. Imaging studies demonstrate that the two agents have a long residence time, showing MR signal enhancement in the liver for more than 40 min, longer than commercially available contrast agents. In vivo and in vitro assays showed that GdW10 and Gd(PW11)2 are promising liver-specific MRI contrast agents and GdW10 may be used in the diagnosis of the pathological state. However, with the higher acute toxicity, the two gadolinium polyoxometalates need to be modified and studied further before clinical use.

70

Abstract 71

Title: Undifferentiated (embryonal) sarcoma of the liver (USL): MRI findings including dynamic gadolinium enhancement

Authors: Evlampia A Psathaa, Richard C Semelka, Lynn Fordhama, Zeynep Firata, John T Woosley

Source: Magnetic Resonance Imaging Volume 22, Issue 6, July 2004, Pages 897–900


Subjects:

Author Supplied Keywords: Embryonal sarcoma; Undifferentiated sarcoma; Liver; Children; MRI

Abstract: We report the MR appearance of undifferentiated (embryonal) sarcoma of the liver (USL) in a 13-year-old female who presented with a 1-year history of intermittent abdominal pain, weight loss, and fatigue. The tumor was a large, solitary, well-defined focal mass lesion with multiple cystic spaces, septations, and substantial central necrosis.

71

Abstract 72

Title: In vivo MRI and ex vivo quantification of iron and Kupffer cells demonstrate residual phagocytic activity in mouse liver after a gadolinium chloride injection

Authors: Monique Fabre, b, Anne Leroy-Willig, Cécile V. Denis, Nathalie Bae, Damien Schoëvaërt, g, Catherine Guettier, Danielle Geldwerth-Feniger

Source: Biochimie Volume 92, Issue 10, October 2010, Pages 1343–1353


Subjects:

Author Supplied Keywords: F4/80 antigen; Ferumoxide; Proton transverse relaxation rate; Lanthanide hepatic toxicity; Macrophages

Abstract: Kupffer cells (KCs), the resident macrophages of the liver, display a phagocytic activity that is not well quantified in animal models. Its experimental invalidation in rodents has been carried out by various means, among which the gadolinium chloride (GdCl3) injection has been widely used, and has been generally monitored by ex vivo techniques. The aim of our study was to determine the KC phagocytic activity induced in mouse liver following a single GdCl3 injection, through Magnetic Resonance Imaging (MRI) measurement of liver uptake of Ferumoxidein vivo, and through ex vivo quantification of Perls positive and F4/80 labeled macrophages. In this study, we showed that 24 h after an IV injection at a dose of 50 mg/kg body weight, GdCl3 did not induce any hepato-cellular damage, nor did it strongly suppress liver phagocytic activity, as demonstrated by the persistent hepatic uptake of the iron-based MRI contrast agent Ferumoxide. In the GdCl3-treated mice, the injection of Ferumoxide produced an increase in the liver proton transverse relaxation rate R2 which averaged 71 ± 24% of that of the control animals. The ex vivo iron and immune phenotypic quantification, performed after the Ferumoxide injection and MRI, confirmed the presence of activated phagocytes in the liver of the GdCl3-treated animals, with a global iron score and F4/80 positive cell count respectively averaging 85 ± 26% and 46 ± 13% of their values in the untreated mice. In vivo MRI evaluation of the liver phagocytic activity using Ferumoxide may further prove useful in the follow up of both experimental and human pathologies

72

Abstract 73

Title: Comparison between GdDTPA and two gadolinium polyoxometalates as potential MRI contrast agents

Authors: Jianghua Fenga, Guoying Suna, Fengkui Peia, Maili Liu

Source: Journal of Inorganic Biochemistry Volume 92, Issues 3–4, 25 November 2002, Pages 193–1


Subjects:

Author Supplied Keywords: Lanthanide polyoxometalates; Relaxivity; MRI; Contrast agent

Abstract: Two gadolinium polyoxometalates, Gd2P2W18O62 and K15[(GdO)3(PW9O34)2], have been evaluated by in vivo as well as in vitro experiments as the candidates of tissue-specific magnetic resonance imaging (MRI) contrast agents. T1-relaxivities of 28.4 mM−1·s−1 for Gd2P2W18O62 and 11.2 mM−1·s−1 for K15[(GdO)3(PW9O34)2] (400 MHz, 25 °C) were higher than that of the commercial MRI contrast agent (GdDTPA). Their relaxivities in bovine serum albumin and human serum transferrin were also reported. The favorable liver-specific contrast enhancement and renal excretion capability in in vivo MRI with Sprague–Dawley rats after i.v. administration of K15[(GdO)3(PW9O34)2] was demonstrated. In vivo and in vitro assay showed that K15[(GdO)3(PW9O34)2] is a promising liver-specific MRI contrast agent. However, Gd2P2W18O62 did not show the favorable quality in vivo as expected from its high relaxivity in vitro, which was attributed to low bioavailability, indicating that it is of limited value as tissue-specific MRI contrast agent.

73

Abstract 74

Title: Serial gadolinium-DTPA of spinal cord MRI in multiple sclerosis: triple vs. single dose

Authors: Indra Yousryb, Massimo Filippia, Ernst Waltherb, Claudio Gasperinic, Ruggero Caprad, Tarek A. Yousry

Source: Magnetic Resonance Imaging Volume 18, Issue 9, November 2000, Pages 1183–1186


Subjects:

Author Supplied Keywords: Comparative studies; Multiple sclerosis; Spinal cord; Contrast enhancement; Gadolinium-DTPA; Triple dose

Abstract: We compared the sensitivity of single and triple dose Gd-DTPA magnetic resonance imaging (MRI) in detecting enhancing lesions in the spinal cord (SC) from 15 patients with multiple sclerosis (MS). The patients were examined monthly on four occasions. We detected two enhancing lesions in two of 15 (13%) patients when a single dose of Gd-DTPA was used. No additional lesions were detected when a triple dose of Gd-DTPA was used. These results 1) confirm that enhanced spinal cord imaging does not significantly increase the detection of active lesions in MS, 2) they do not support the general application of triple dose Gd-DTPA when examining the SC but 3) suggest that further studies taking into account SC symptoms are necessary.

74

Abstract 75

Title: Short-term evolution of new multiple sclerosis lesions enhancing on standard and triple dose gadolinium-enhanced brain MRI scans

Authors: Marco Rovarisa, Giovanna Mastronardoa, Francesca Prandinib, Stefano Bastianelloc, Giancarlo Comid, Massimo Filippi

Source: Journal of the Neurological Sciences Volume 164, Issue 2, 1 April 1999, Pages 148–152


Subjects:

Author Supplied Keywords: Multiple sclerosis; Magnetic resonance imaging; Gadolinium enhancement; Lesion evolution

Abstract: We compared the short-term magnetic resonance imaging (MRI) evolution of new multiple sclerosis (MS) lesions enhancing after single dose (SD) (0.1 mmol/kg) or triple dose (TD) (0.3 mmol/kg) gadolinium–DTPA (Gd) to explore possible differences in the pathological substrates of acute MS lesions. Brain MRI scans were obtained at baseline and every 4 weeks for a 3-month period in 18 relapsing-remitting MS patients. At each time point, using two separate sessions, we obtained dual echo and T1-weighted scans before and after SD and TD of Gd. New enhancing lesions detected at month 1 and 2 were entered into the analysis. The presence of corresponding hypointense lesions on unenhanced T1-weighted scans and hyperintense lesions on T2/proton density (PD)-weighted images was assessed on the same scan and on the scans performed 1 month before and 1 month after the new lesion development. Persistence of enhancement was evaluated on the SD and TD scans obtained 1 month after new lesion appearance. One-hundred and sixty lesions were studied. Of these, 97 lesions were enhancing after both SD and TD (group A) and 63 lesions only after TD (group B). Thirty (31%) of the lesions enhancing after both SD and TD and ten (16%) of the lesions enhancing only after TD had corresponding T1-weighted lesions (P=0.03). Of these lesions, 87% in group A and 40% in group B (P=0.003) were not hypointense on the previous scans. No differences were found in the frequencies of corresponding T2/PD-weighted abnormalities (92% in Group A vs. 87% in Group B lesions). Of these hyperintense areas, 62% in group A and 56% in group B were not present on the previous scans. On follow-up scans, 52% of the lesions enhancing after SD and TD and 70% of the lesions enhancing only after TD did not show enhancement after the injection of both the doses of Gd (P=0.02). The frequencies of corresponding T2/PD and T1-weighted abnormalities were higher in Group A than in Group B lesions, but the differences were not statistically significant. Our findings suggest that the pathological process is less severe in MS lesions enhancing only after TD injection than in those enhancing after the SD.

75

Abstract 76

Title: Triple dose of gadolinium-DTPA increases the sensitivity of spinal cord MRI in detecting enhancing lesions in multiple sclerosi

Authors: Tarek A Yousry, Gunter Fesl, Ernst Walther, Raymond Voltz, Massimo Filippi

Source: Journal of the Neurological Sciences Volume 158, Issue 2, 30 June 1998, Pages 221–225


Subjects:

Author Supplied Keywords: Magnetic resonance; Comparative studies; Multiple sclerosis; Spinal cord; Contrast enhancement; Gadolinium-DTPA; Triple dose

Abstract: We compared the sensitivity of single and triple dose Gd-DTPA magnetic resonance imaging (MRI) in detecting enhancing lesions in the spinal cord of 13 patients with multiple sclerosis (MS). We detected two enhancing lesions in two of 13 (15%) patients when the single dose of Gd-DTPA was used and 12 lesions in five of 13 (38%) patients when the triple dose of Gd-DTPA was used. These results suggest that: (1) the use of triple dose increases the sensitivity of spinal cord MRI when studying relapsing–remitting or secondary progressive MS patients, (2) triple dose Gd-DTPA enhanced of the spinal cord MRI might be useful in monitoring disease activity in patients with MS.

76

Abstract 77

Title: Gadolinium-labeled liposomes containing amphiphilic Gd-DTPA derivatives of varying chain length: Targeted MRI contrast enhancement agents for the liver

Authors: G.W. Kabalka, M.A. Davis, E. Holmberg, K. Maruyama‡, L. Huang



Subjects:

Author Supplied Keywords: Liposomes; Gadolinium; MRI; Amphiphiles

Abstract: Paramagnetic liposomal contrast agents were synthesized and utilized for selective

augmentation of T1MR imaging of the livers of normal mice. Amphiphilic gadolinium complexes, which mimic phospholipids, were incorporated into the lamella of small unilamellar liposomes (SUV) such that they become an integral part of its surface. The amphiphilic complexing agents consisted of DTPA reagents in which a pair of alkyl chains of varying lengths are attached via amide linkages. The in vivo lifetimes of the amphiphilic agents were found to be dependent on the chain length of the alkyl groups.

77

Abstract 78

Title: Primary lymphoma of the cervix: MRI findings with gadolinium

Authors: Hong T. Dang∗, Michael R. Terk, †, Patrick M. Colletti†, John B. Schlaerth‡, John P. Curtin‡



Subjects:

Author Supplied Keywords: Pelvis, MRI; Lymphoma; Cervix, MRI; Contrast enhancement; Gadolinium DTPA

Abstract: MRI evaluation of primary cervical lymphoma has not been reported. We report such a case of primary cervical lymphoma, a lesion well seen and well delineated from normal tissue by MRI. Although primary lymphoma of the cervix is a rare entity, the disease does exist and can be well demonstrated by MRI. We evaluated the MR appearance of this lesion with both non-enhanced and gadolinium-enhanced imaging.

78

Abstract 79

Title: Dynamic MRI of the pancreas — Gadolinium enhancement in normal tissue

Authors: J. Brailsford, J. Ward, A.G. Chalmers, J. Ridgway, P.J. Robinson

Source: Clinical Radiology Volume 49, Issue 2, February 1994, Pages 104–108


Subjects:


Abstract: The purpose of this study was to measure signal enhancement over time in the normal pancreas after intravenous bolus infection of gadolinium-DTPA (Schering Health Care Ltd) (Gd-DTPA). Data was obtained from 25 patients with no evidence of pancreatic disease before, immediately after and over a 2 min period following injection of Gd-DTPA (Magnevist 0.2 ml per kg). Scans were obtained using a turbo-FLASH sequence which allows 11 slices to be acquired during a single breath hold period of 19 s. Five mm thick slices were acquired in the coronal/oblique plane at 0.5 mm intervals. A pre-contrast block of slices was obtained followed by dynamic post-contrast scanning with the first of four acquisitions beginning 12–15 s after bolus injection. A 10 s interval between each acquisition was selected to allow the patients to breathe. Signal intensity for each acquisition was measured for the pancreatic head and tail and also for the liver. All values were normalized to fat. Marked enhancement of the pancreas was seen in all cases with peak enhancement occurring in the first and second post-contrast acquisition. The pancreatic duct was more easily seen after contrast injection.

79

Abstract 80

Title: Evaluation of two new gadolinium chelates as contrast agents for MRI

Authors: Carol B. Wiegers, Michael J. Welch, Terry L. Sharp, Jeffrey J. Brown, William H. Perman, Yizhen Sun, Ramunas J. Motekaitis, Arthur E. Martell



Subjects:

Author Supplied Keywords: Gadolinium; Chelates; Enhancement agents; Kidney; Liver

Abstract: Two new gadolinium chelates were investigated for potential use as tissue-specific contrast agents for magnetic resonance imaging. In vitro measurements of stability constants, octanol/water partition coefficients and relaxation times in solutions of water and human serum albumin (HSA) were performed with each new chelate and compared with gadolinium-diethylenetriamine pentaacetic acid, Gd(DTPA). Biodistribution studies and magnetic resonance imaging in rats were used to evaluate the new chelates in vivo. The stability constants (log K) of gadolinium-N,N″-bis(3-hydroxy-6-methyl-2-pyridylmethyl)diethylenetriamine-N,N ,N″′ -triacetic acid, Gd(DTTA-HP), and gadolinium-1,7-13-triaza-4,10-16-trioxacyclooctadecane-N,N ,N″′ -triacetic acid, Gd(TTCT), were determined to be 23.65 and 18.07, respectively. These can be compared to a literature value of 22.46 for Gd(DTPA). Octanol/water partition coefficients for both complexes showed they were more lipophilic than Gd(DTPA). Gd(DTTA-HP) exhibited a smaller relaxivity in water but a larger relaxivity in 4% HSA than Gd(DTPA). Gd(TTCT) exhibited a lower relaxivity than Gd(DTPA) in both water and 4% HSA. Both complexes showed similar biodistributions to Gd(DTPA) no carrier-added concentrations. Gd(DTTA-HP) had a greater percent change in signal intensity than Gd(DTPA) on T1-weighted spin-echo images in the heart, liver, and kidney. Percent change in signal intensity for Gd(TTCT) was lower than Gd(DTPA) in heart, liver, and kidney.

80

Abstract 81

Title: MRI of normal and abnormal duodenum using half-fourier single-shot RARE and gadolinium-enhanced spoiled gradient echo sequences

Authors: Hani B Marcos∗, Richard C Semelka, Tara C Noone∗, John T Woosley†, Joseph K.T Lee



Subjects:

Author Supplied Keywords: Duodenum; Contrast enhancement; Spoiled-gradient echo (SGE); Half-Fourier Acquisition Single-shot RARE (HASTE).

Abstract: The objective of this research was two-fold: First, to describe the normal and abnormal MR appearances of the duodenum using combined Half-Fourier Acquisition Single Shot RARE (HASTE) and gadolinium-enhanced standard and fat suppressed spoiled gradient echo (SGE) sequences. The second objective was to assess the ability of these combined sequences to detect and characterize duodenal diseases. MR examinations were performed on fifty consecutive patients with no clinical history of duodenal diseases, who were 1) imaged with HASTE and gadolinium-enhanced standard and fat suppressed SGE sequences and 2) referred to MR examination for reasons other than duodenal diseases, and were reviewed retrospectively to determine the normal MR appearances of the duodenum. A second population of patients with abnormal duodenum who were imaged with the same MR sequences were included in the second part of this study. This population was composed of 20 consecutive patients with subsequently proven duodenal abnormalities, including: malrotation (2), diverticula (4), intussusception (1), sprue (1), polyps (2), neurofibroma (1), lymphoma (1), Zollinger Ellison syndrome (1), metastatic disease (1), Crohn’s disease (1), and wall thickening and duodenitis (5). Normal measurements of the duodenum are described. Abnormalities of wall thickness and duodenal masses required combined HASTE and gadolinium-enhanced SGE images to evaluate well. Abnormalities of the bowel lumen (e.g., diverticula and intussusception), and developmental variants (e.g., malrotation), were sufficiently visualized on HASTE images alone. Bowel inflammation was best shown on gadolinium-enhanced fat suppressed SGE images. HASTE and gadolinium-enhanced fat suppressed SGE sequences are complementary techniques for the demonstration of normal and abnormal duodenum. The combined use of both sequences allows evaluation of different aspects of bowel diseases; abnormalities of position, lumen, and contents are well shown on HASTE, while inflammation is best shown on gadolinium enhanced fat suppressed SGE, and wall thickening and masses are best evaluated with the combined use of both techniques.

81

Abstract 82

Title: Dark Regions of No-Reflow on Late Gadolinium Enhancement Magnetic Resonance Imaging Result in Scar Formation After Atrial Fibrillation Ablation

Authors: Christopher McGann, MD, Eugene Kholmovski, PhD, Joshua Blauer, BS, Sathya Vijayakumar, MS, Thomas Haslam, BS, Joshua Cates, PhD, Edward DiBella, PhD, Nathan Burgon, BS, Brent Wilson, MD, PhD, Alton Alexander, BS, Marcel Prastawa, PhD, Marcos Daccarett, MD, Gaston Vergara, MD, Nazem Akoum, MD, Dennis Parker, PhD, Rob MacLeod, PhD, Nassir Marrouche, MD

Source: Journal of the American College of Cardiology Volume 58, Issue 2, 5 July 2011, Pages 177–185


Subjects:

Author Supplied Keywords: ablation; atrium; fibrosis; magnetic resonance imaging

Abstract: The aim of this study was to assess acute ablation injuries seen on late gadolinium enhancement (LGE) magnetic resonance imaging (MRI) immediately post-ablation (IPA) and the association with permanent scar 3 months post-ablation (3moPA). Success rates for atrial fibrillation catheter ablation vary significantly, in part because of limited information about the location, extent, and permanence of ablation injury at the time of procedure. Although the amount of scar on LGE MRI months after ablation correlates with procedure outcomes, early imaging predictors of scar remain elusive. Thirty-seven patients presenting for atrial fibrillation ablation underwent high-resolution MRI with a 3-dimensional LGE sequence before ablation, IPA, and 3moPA using a 3-T scanner. The acute left atrial wall injuries on IPA scans were categorized as hyperenhancing (HE) or nonenhancing (NE) and compared with scar 3moPA. Heterogeneous injuries with HE and NE regions were identified in all patients. Dark NE regions in the left atrial wall on LGE MRI demonstrate findings similar to the “no-reflow” phenomenon. Although the left atrial wall showed similar amounts of HE, NE, and normal tissue IPA (37.7 ± 13%, 34.3 ± 14%, and 28.0 ± 11%, respectively; p = NS), registration of IPA injuries with 3moPA scarring demonstrated that 59.0 ± 19% of scar resulted from NE tissue, 30.6 ± 15% from HE tissue, and 10.4 ± 5% from tissue identified as normal. Paired t-test comparisons were all statistically significant among NE, HE, and normal tissue types (p < 0.001). Arrhythmia recurrence at 1-year follow-up correlated with the degree of wall enhancement 3moPA (p = 0.02). Radiofrequency ablation results in heterogeneous injury on LGE MRI with both HE and NE wall lesions. The NE lesions demonstrate no-reflow characteristics and reveal a better predictor of final scar at 3 months. Scar correlates with procedure outcomes, further highlighting the importance of early scar prediction.

82

Abstract 83

Title: Incidental LV Late Gadolinium Enhancement on CMR Imaging in Atrial Fibrillation Predicts Recurrence After Ablation Therapy

Authors: Promporn Suksaranjit, MD∗, †, Nazem Akoum, MD∗, †, Eugene G. Kholmovski, PhD†, ‡, Gregory J. Stoddard, MS§, Lowell Chang, MD∗, †, Kavitha Damal, PhD§, Krishna Velagapudi, MD∗, Allen Rassa, MD∗, Erik Bieging, MD∗, Shridhar Challa, MD∗, Imran Haider, MD∗, †, Nassir F. Marrouche, MD∗, †, Christopher J. McGann, MD∗, †, Brent D. Wilson, MD, PhD

Source:


Subjects:

Author Supplied Keywords: ablation therapy; atrial fibrillation; cardiac magnetic resonance; late gadolinium enhancement

Abstract: This study sought to evaluate the prognostic significance of left ventricular late gadolinium enhancement (LV-LGE) incidentally found in atrial fibrillation (AF) patients who undergo ablation therapy. LV-LGE provides prognostic information in patients with ischemic and non-ischemic cardiomyopathies. However, data on the clinical significance of incidental LV-LGE in the AF population are limited. A total of 778 patients who were referred for radiofrequency ablation of AF underwent cardiac magnetic resonance examinations between June 2006 and January 2013. Patients with a history of myocardial infarction or ablation therapy were excluded. The presence of LV-LGE was assessed by experienced imaging physicians. Patients were followed for arrhythmia recurrence after the radiofrequency ablation procedure. Of 598 patients included in the study, 60% were men with a mean age of 64 years and a median AF duration of 25 months. LV-LGE was detected in 39 patients (6.5%). There were 240 arrhythmia recurrences observed involving 40% of patients over a median follow-up period of 52 months. On univariate analysis, age (hazard ratio [HR]: 1.02; 95% confidence interval [CI]: 1.00 to 1.03), male sex (HR: 0.63; 95% CI: 0.47 to 0.86), diabetes (HR: 1.53; 95% CI: 1.03 to 2.27), CHADS2 score (HR: 1.19; 95% CI: 1.04 to 1.36), CHA2DS2-VASc score (HR: 1.18; 95% CI: 1.08 to 1.30), left atrial (LA) fibrosis (HR: 1.66; 95% CI: 1.41 to 1.96), LV-LGE (HR: 1.83; 95% CI: 1.11 to 3.03), persistent AF (HR: 1.52; 95% CI: 1.11 to 2.09), and LA area (HR: 1.03; 95% CI: 1.01 to 1.05) were significantly associated with arrhythmia recurrence. The recurrence rate was 69% in patients with LV-LGE compared with 38% in patients without LV-LGE (p < 0.001). In a multivariate model, LA fibrosis and LV-LGE were independent predictors of arrhythmia recurrence. In AF patients without history of myocardial infarction, LV-LGE is a significant independent predictor of arrhythmia recurrence after ablation therapy.

83

Abstract 84

Title: Effect of gadolinium injection on diffusion-weighted imaging with background body signal suppression (DWIBS) imaging of breast lesions

Authors: Marco Moschetta, Michele Telegrafo, Leonarda Rella, Amato Antonio Stabile Ianora, Giuseppe Angelelli

Source: Magnetic Resonance Imaging Volume 32, Issue 10, December 2014, Pages 1242–1246


Subjects:

Author Supplied Keywords: Breast; DWIBS; Diffusion; MRI; Gadolinium

Abstract: Diffusion-weighted imaging with background body signal suppression (DWIBS) provides both qualitative and quantitative imaging of breast lesions and are usually performed before contrast material injection (CMI). This study aims to assess whether the administration of gadolinium significantly affects DWIBS imaging. 200 patients were prospectively evaluated by MRI with STIR, TSE-T2, pre-CMI DWIBS, contrast enhanced THRIVE-T1 and post-CMI DWIBS sequences. Pre and post-CMI DWIBS were analyzed searching for the presence of breast lesions and calculating the ADC value. ADC values of ≤ 1.44 × 10- 3 mm2/s were considered suspicious for malignancy. This analysis was then compared with the histological findings. Sensitivity, specificity, diagnostic accuracy (DA), positive predictive value (PPV) and negative (NPV) were calculated for both sequences and represented by ROC analysis. Pre and post-CMI ADC values were compared by using the paired t test. In 150/200 (59%) patients, pre and post-CMI DWIBS indicated the presence of breast lesions, 53 (35%) with ADC values of > 1.44 × 10- 3 mm2/s and 97 (65%) with ADC ≤ 1.44 × 10- 3 mm2/s. Pre-CMI and post-DWIBS sequences obtained the same sensitivity, specificity, DA, PPV and NPV values of 97%, 83%, 89%, 79% and 98%. The mean ADC value of benign lesions was 1.831 ± 0.18 × 10- 3 mm2/s before and 1.828 ± 0.18 × 10- 3 mm2/s after CMI. The mean ADC value of the malignant lesions was 1.146 ± 0.16 × 10- 3 mm2/s before and 1.144 ± 0.16 × 10- 3 mm2/s after CMI. No significant difference was found between pre and post CMI ADC values (p > 0.05). DWIBS imaging is not influenced by CMI. Breast MR protocol could be modified by placing DWIBS after dynamic contrast enhanced sequences in order to maximize patient cooperation.

84

Abstract 85

Title: T2* mapping and delayed gadolinium-enhanced magnetic resonance imaging in cartilage (dGEMRIC) of humeral articular cartilage—a histologically controlled study

Authors: Bernd Bittersohl, MD, Jörn Kircher, MD, PhD, Falk R. Miese, MD, Christin Dekkers, MD, Peter Habermeyer, MD, Julia Fröbel, PhD, Gerald Antoch, MD, Rüdiger Krauspe, MD, Christoph Zilkens, MD

Source: Journal of Shoulder and Elbow Surgery 7 May 2015


Subjects:

Author Supplied Keywords: T2*; dGEMRIC; MRI; cartilage; shoulder; histology

Abstract: Cartilage biochemical imaging modalities that include the magnetic resonance imaging (MRI) techniques of T2* mapping (sensitive to water content and collagen fiber network) and delayed gadolinium-enhanced MRI of cartilage (dGEMRIC, sensitive to the glycosaminoglycan content) can be effective instruments for early diagnosis and reliable follow-up of cartilage damage. The purpose of this study was to provide T2* mapping and dGEMRIC values in various histologic grades of cartilage degeneration in humeral articular cartilage. A histologically controlled in vitro study was conducted that included human humeral head cartilage specimens with various histologic grades of cartilage degeneration. High-resolution, 3-dimensional (3D) T2* mapping and dGEMRIC were performed that enabled the correlation of MRI and histology data. Cartilage degeneration was graded according to the Mankin score, which evaluates surface morphology, cellularity, toluidine blue staining, and tidemark integrity. SPSS software was used for statistical analyses. Both MRI mapping values decreased significantly (P < .001) with increasing cartilage degeneration. Spearman rank analysis revealed a significant correlation (correlation coefficients ranging from −0.315 to 0.784; P < .001) between the various histologic parameters and the T2* and T1Gd mapping values. This study demonstrates the feasibility of 3D T2* and dGEMRIC to identify various histologic grades of cartilage damage of humeral articular cartilage. With regard to the advantages of these mapping techniques with high image resolution and the ability to accomplish a 3D biochemically sensitive imaging, we consider that these imaging techniques can make a positive contribution to the currently evolving science and practice of cartilage biochemical imaging.

85

Abstract 86

Title: Low-intensity late gadolinium enhancement predominates in hypertrophic cardiomyopathy

Authors: David M. Naeger, Charles Higgins, Teresa De Marco, Stefano Muzzarelli, Karen G. Ordovas

Source: Clinical Imaging Volume 39, Issue 3, May–June 2015, Pages 432–436


Subjects:

Author Supplied Keywords: Late gadolinium enhancement; LGE; DCE; Hypertrophic cardiomyopathy; HCM

Abstract: Assess the extent of low- versus high-intensity late gadolinium enhancement (LGE) in hypertrophic cardiomyopathy (HCM). Low- versus high-intensity LGE indexed volumes in 19 HCM patients were compared to 23 myocardial infarction (MI) patients. Total, low-, and high-intensity LGE volumes in HCM vs. MI were 7.6 ml/m2, 4.7, and 2.4 vs. 11.2, 2.5, and 7.1, respectively. Total LGE volume did not differ (P= .13), though low- and high-intensity did (P= .05, .004). 67% versus 26% of all LGE was low-intensity in HCM versus MI (P< .001). LGE in HCM is predominantly low-intensity, so a low threshold may be the most appropriate.

86

Abstract 87

Title: Device artifact reduction for magnetic resonance imaging of patients with implantable cardioverter-defibrillators and ventricular tachycardia: Late gadolinium enhancement correlation with electro-anatomic mapping

Authors: Steven M. Stevens, MD*, Roderick Tung, MD, FHRS*, Shams Rashid, PhD†, Jean Gima, NP*, Shelly Cote, NP*, Geraldine Pavez, NP*, Sarah Khan, MD†, Daniel B. Ennis, PhD†, J. Paul Finn, MD†, Noel Boyle, MD, PhD, FHRS*, Kalyanam Shivkumar, MD, PhD, FHRS*, †, Peng Hu, PhD

Source: Heart Rhythm Volume 11, Issue 2, February 2014, Pages 289–298


Subjects:

Author Supplied Keywords: Ventricular tachycardia; Delayed enhancement; Magnetic resonance imaging; Implantable cardioverter-defibrillator; Image artifact; Myocardial scar; Electro-anatomic mapping; Late gadolinium enhancement; Catheter ablation; Arrhythmia; Clinical electrophysiology; Ablation

Abstract: Late gadolinium enhancement (LGE) magnetic resonance imaging (MRI) of ventricular scar has been shown to be accurate for detection and characterization of arrhythmia substrates. However, the majority of patients referred for ventricular tachycardia (VT) ablation have an implantable cardioverter-defibrillator (ICD), which obscures image integrity and the clinical utility of MRI. The purpose of this study was to develop and validate a wideband LGE MRI technique for device artifact removal. A novel wideband LGE MRI technique was developed to allow for improved scar evaluation on patients with ICDs. The wideband technique and the standard LGE MRI were tested on 18 patients with ICDs. VT ablation was performed in 13 of 18 patients with either endocardial and/or epicardial approach and the correlation between the scar identified on MRI and electro-anatomic mapping (EAM) was analyzed. Hyper intensity artifact was present in 16 of 18 of patients using standard MRI, which was eliminated using the wideband LGE and allowed for MRI interpretation in 15 of 16 patients. All patients had ICD lead characteristics confirmed as unchanged post-MRI and had no adverse events. LGE scar was seen in 11 of 18 patients. Among the 15 patients in whom wideband LGE allowed visualization of myocardium, 10 had LGE scar and 5 had normal myocardium in the regions with image artifacts when using the standard LGE. The left ventricular scar size measurements using wideband MRI and EAM were correlated with R2 = 0.83 and P = .00003. Wideband LGE MRI improves the ability to visualize myocardium for clinical interpretation, which correlated well with EAM findings during VT ablation.

87

Abstract 88

Title: Pharmacokinetics of gadoversetamide injection, a gadolinium-based contrast agent, in pediatric patients

Authors: James H. Wible Jr., Prasad N.V. Tata, Alicia M. Napoli, Lisa H. Lowe, Gregory L. Kearns

Source: Magnetic Resonance Imaging Volume 27, Issue 4, May 2009, Pages 512–518


Subjects:

Author Supplied Keywords: Gadoversetamide; OptiMARK; Pharmacokinetics; Gadolinium; MRI Contrast agents; Pediatric patients

Abstract: The pharmacokinetics of gadoversetamide were examined in pediatric patients scheduled to undergo contrast-enhanced MRI of the central nervous system. One hundred patients received an intravenous injection of gadoversetamide at a dose of 0.1 mmol/kg for a contrast-enhanced MRI procedure. A subpopulation of 30 patients were enrolled to evaluate the pharmacokinetics of gadoversetamide in patients 2–11 and 12–18 years of age. Serial blood and urine samples were collected before and after the administration of gadoversetamide. The terminal half-life, initial concentration and area under the curve assessments for gadoversetamide showed no significant (P>.05) differences between the age groups or the sexes. Although no sex-related differences occurred in the volume of distribution or clearance, significant (P<.05) age-related differences were found, but once corrected for body mass or surface area the differences were no longer significant. The pharmacokinetic behavior of gadoversetamide was not significantly altered by differences in age or sex in pediatric patients from 2 to 18 years of age. Although significant differences in volumes of distribution, and clearance occurred between the age groups, these differences appeared to depend on body size rather than on age in pediatric patients between 2 and 18 years of age.

88

Abstract 89

Title: Association of Gadolinium Based Magnetic Resonance Imaging Contrast Agents and Nephrogenic Systemic Fibrosis

Authors: Gautam Bhave, Julia B. Lewis, Sam S. Chang

Source: The Journal of Urology Volume 180, Issue 3, September 2008, Pages 830–835


Subjects:

Author Supplied Keywords: gadolinium; kidney diseases; magnetic resonance imaging

Abstract: We investigated the recently discovered association between gadolinium based magnetic resonance imaging contrast agents and the development of nephrogenic systemic fibrosis in patients with chronic kidney disease or acute kidney injury. A systematic review of the PubMed® database and publicly available patient databases was performed to characterize nephrogenic systemic fibrosis and its possible association with exposure to gadolinium based magnetic resonance imaging contrast agents. Data from case series reports, nephrogenic systemic fibrosis patient databases, nephrogenic systemic fibrosis case reporting to the Food and Drug Administration after gadolinium contrast agent exposure and retrospective case control studies suggest a strong association between the uses of gadolinium based magnetic resonance imaging contrast agents and the subsequent development of nephrogenic systemic fibrosis in patients with renal disease. These data also suggest that the risk of nephrogenic systemic fibrosis depends on the degree of renal dysfunction, dose of contrast agent, gadolinium contrast agent stability and severity of concomitant illness. Thus, the occurrence of nephrogenic systemic fibrosis after gadolinium contrast agent exposure may vary from negligible up to 2% to 5% in select high risk clinical situations. Magnetic resonance imaging using gadolinium based contrast agents must be performed judiciously in patients with renal dysfunction, carefully weighing on a case by case basis the benefits of magnetic resonance imaging and the risk of nephrogenic systemic fibrosis as well as the disadvantages of undergoing alternative or foregoing imaging studies.

89

Abstract 90

Title: Supramolecular aggregates containing lipophilic Gd(III) complexes as contrast agents in MRI

Authors: Antonella Accardo, Diego Tesauro, Luigi Aloj, Carlo Pedone, Giancarlo Morelli

Source: Coordination Chemistry Reviews Volume 253, Issues 17–18, September 2009, Pages 2193–2213


Subjects:

Author Supplied Keywords: Amphiphilic gadolinium complexes; MRI contrast agents; Micelles; Liposomes; Target-selective contrast agents

Abstract: Magnetic resonance imaging (MRI) contrast agents based on paramagnetic gadolinium complexes are widely used in biomedical research and diagnosis. Their application is intended to improve efficacy of MRI providing physiological information along with the impressive anatomical detail already obtained by images without contrast. The classical gadolinium complexes currently used for MRI contrast enhancement are all low molecular weight compounds that rapidly equilibrate between the intra and extravascular spaces after intravenous administration. In order to obtain gadolinium-based agents with different pharmacokinetic properties, supramolecular aggregates such as micelles and liposomes have been recently proposed. Micelles and liposomes, obtained by the aggregation of lipophilic gadolinium complexes are here described, with the aim to correlate their structural and relaxometric properties. We report on the state of the art in the development of supramolecular aggregates obtained by self-assembly of lipophilic gadolinium complexes and aggregates in which lipophilic gadolinium complexes are assembled with surfactants. Moreover aggregates derivatized with bioactive molecules, such as peptides and antibodies, acting as target selective MRI contrast agents are described.

90

Abstract 91

Title: Inflammatory Abdominal Aortic Aneurysms: Diagnosis with Gadolinium Enhanced T1-Weighted Imaging

Authors: F. Wallis, G.H. Roditi, T.W. Redpath, J. Weir, K.S. Cross, F.W. Smith

Source: Clinical Radiology Volume 55, Issue 2, February 2000, Pages 136–139


Subjects:

Author Supplied Keywords: inflammatory abdominal aortic aneurysm, gadolinium, MRI

Abstract: Inflammatory abdominal aortic aneurysms (IAAA) are a variant of abdominal aortic aneurysms, which are associated with an increased morbidity. The diagnosis of IAAA has traditionally been established with a combination of clinical and laboratory findings together with contrast enhanced CT. There is a high incidence of renal impairment in this group, and therefore contrast enhanced CT may be harmful. Five patients with IAAA underwent T1-weighted spin echo and gradient echo gadolinium enhanced abdominal MRI. A total of eight examinations were performed, including three patients who underwent repeat MRI following steroid therapy. The inflammatory cuff was clearly identified following gadolinium administration in all eight examinations. The cuff enhanced homogeneously in all patients with no alteration in appearance following steroid therapy. The intravenous administration of gadolinium DTPA enabled clearer definition of locally involved structures. Gadolinium enhanced MRI readily demonstrates features of IAAA. In view of potential renal impairment in this patient group, we recommend this technique in preference to contrast enhanced CT in the initial investigation of inflammatory abdominal aortic aneurysms.

91

Abstract 92

Title: A new biodegradable and biocompatible gadolinium (III) -polymer for liver magnetic resonance imaging contrast agent

Authors: Yan Xiao, Rong Xue, Tianyan You, Xiaojing Li, Fengkui Pei



Subjects:

Author Supplied Keywords: MRI contrast agent; Gadolinium (III) -polymer; Liver; Relaxivity; Biocompatibility

Abstract: A new biodegradable and biocompatible gadolinium (III) -copolymer (ACL-A2-DOTA-Gd) has been developed as a potential liver magnetic resonance imaging (MRI) contrast agent. ACL-A2-DOTA-Gd consisted of a poly (aspartic acid-co-leucine) unit bound with 1,4,7,10-tetraazacyclododecan-1,4,7,10-tetraacetic acid-gadolinium (Gd-DOTA) via the linkage of ethylenediamine. In vitro, the biodegradable experiment and cytotoxicity assay showed the biodegradability and biocompatibility of this gadolinium-polymer. ACL-A2-DOTA-Gd presented an increase in relaxivity of 2.4 times than the clinical Gd-DOTA. In vivo, gadolinium (III)-copolymer was mainly accumulated in the liver, and it could be excreted via the renal and hepatobiliary mechanism. The average enhancement of ACL-A2-DOTA-Gd (60.71 ± 5.93%, 50–80 min) in liver was 2.62-fold greater than that of Gd-DOTA (23.16 ± 3.55%, 10–30 min). ACL-A2-DOTA-Gd could be as a potential liver MRI contrast agent with a long time-window.

92

Abstract 93

Title: Dual Contrast Enhanced Magnetic Resonance Imaging of the Liver with Superparamagnetic Iron Oxide Followed by Gadolinium for Lesion Detection and Characterization

Authors: Samantha Kubaska, Dushyant V. Sahani, Sanjay Sainif1, Peter F. Hahn, Elkan Halpern

Source:


Subjects:

Author Supplied Keywords: iron oxide, gadolinium, liver, MRI, signal intensity

Abstract: Iron oxide contrast agents are useful for lesion detection, and extracellular gadolinium chelates are advocated for lesion characterization. We undertook a study to determine if dual contrast enhanced liver imaging with sequential use of ferumoxides particles and gadolinium (Gd)-DTPA can be performed in the same imaging protocol. MATERIALS AND METHODS: Sixteen patients underwent dual contrast magnetic resonance imaging (MRI) of the liver for evaluation of known/suspected focal lesions which included, metastases (n = 5), hepatocellular carcinoma (HCC;n = 3), cholangiocharcinoma(n = 1) and focal nodular hyperplasia (FNH;n = 3). Pre- and post-iron oxide T1-weighted gradient recalled echo (GRE) and T2-weighted fast spin echo (FSE) sequences were obtained, followed by post-Gd-DTPA (0.1 mmol/kg) multi-phase dynamic T1-weighted out-of-phase GRE imaging. Images were analyzed in a blinded fashion by three experts using a three-point scoring system for lesion conspicuity on pre- and post-iron oxide T1 images as well as for reader's confidence in characterizing liver lesions on post Gd-DTPA T1 images. RESULTS: No statistically significant difference in lesion conspicuity was observed on pre- and post-iron oxide T1-GRE images in this small study cohort. The presence of iron oxide did not appreciably diminish image quality of post-gadolinium sequences and did not prevent characterization of liver lesions. CONCLUSION: Our results suggest that characterization of focal liver lesion with Gd-enhanced liver MRI is still possible following iron oxide enhanced imaging.

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Abstract 94

Title: Neurotoxicity of gadolinium contrast agents for magnetic resonance imaging in rats with osmotically disrupted blood-brain barrier

Authors: Masaya Takahashi, Hirokazu Tsutsui, Chie Murayama, Tomoaki Miyazawa, Bernhard Fritz-Zieroth



Subjects:

Author Supplied Keywords: Neurotoxicity; Gadolinium complexes; MRI contrast agents; Blood-brain barrier; Animals

Abstract: The neurotoxicity of intravenously injected Gadolinium (Gd) complexes to rats with disrupted blood-brain barrier (BBB) was evaluated. After disruption of the BBB by infusion of mannitol solution, one of several contrast agents tested was injected intravenously at a dose of 1 or 3 mmol Gd/kg, and neurological symptoms were graded. The concentrations of Gd in brain and plasma were also measured. Injection of Gd-DTPA at a dose of 3 mmol Gd/kg did not change behavior. On the other hand, Gd-DTPA-BMA, Gd-DO3A-butrol, and Gd-DO3A-HP each induced behavioral impairments, and some animals died within 1 h after injection. Gd-DO3A-HP showed lethal effect even at a dose of 1 mmol/kg. The concentration of Gd in the brain of the animals injected with Gd-DO3A-HP at 3 mmol Gd/kg was essentially the same as that of animals injected with Gd-DTPA at the same dose. The neurotoxicity of the contrast agents tested was graded as follows: Gd-DTPA ≤ Gd-DTPA-BMA = Gd-DO3A-butrol < Gd-DO3A-HP.

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Abstract 95

Title: Rapid microwave-assisted synthesis of PVP-coated ultrasmall gadolinium oxide nanoparticles for magnetic resonance imaging

Authors: Parisa Vahdatkhah, Hamid Reza Madaah Hosseini, Azin Khodaei, Ali Reza Montazerabadi, Rasoul Irajirad, Mohamad Ali Oghabian, Hamid Delavari H.

Source: Chemical Physics Volumes 453–454, 12 May–1 June 2015, Pages 35–41


Subjects: A rapid microwave-assisted polyol process used to synthesize Gd2O3 nanoparticles.

In situ surface modification of ultrasmall Gd2O3NPs with PVP has been performed.

Gd2O3NPs shows considerable increasing of relaxivity in comparison to Gd-chelates.

PVP-covered Gd2O3NPs show appropriate stability for approximately 15 days.

Spectrophotometric indicates the leaching of free Gd ions not occurred versus tim

Author Supplied Keywords: MRI imaging; Contrast agent; Nanoparticle; Gadolinium oxide; Polyol process; Microwave

Abstract: Synthesis of polyvinyl pyrrolidone (PVP) coated ultrasmall Gd2O3 nanoparticles (NPs) with enhanced T1-weighted signal intensity and r2/r1 ratio close to unity is performed by a microwave-assisted polyol process. PVP coated Gd2O3NPs with spherical shape and uniform size of 2.5 ± 0.5 nm have been synthesized below 5 min and structure and morphology confirmed by HRTEM, XRD and FTIR. The longitudinal (r1) and transversal relaxation (r2) of Gd2O3NPs is measured by a 3 T MRI scanner. The results showed considerable increasing of relaxivity for Gd2O3NPs in comparison to gadolinium chelates which are commonly used for clinical magnetic resonance imaging. In addition, a mechanism for Gd2O3NPs formation and in situ surface modification of PVP-grafted Gd2O3NPs is proposed.

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Abstract 96

Title: Comparison of preexisting and ablation-induced late gadolinium enhancement on left atrial magnetic resonance imaging

Authors: Kotaro Fukumoto, MD, PhD*, Mohammadali Habibi, MD*, Esra Gucuk Ipek, MD*, Irfan M. Khurram, MD*, Stefan L. Zimmerman, MD†, Vadim Zipunnikov, PhD‡, David D. Spragg, MD*, Hiroshi Ashikaga, MD, PhD*, John Rickard, MD*, Joseph E. Marine, MD, FHRS*, Ronald D. Berger, MD, PhD, FHRS*, Hugh Calkins, MD, FHRS*, Saman Nazarian, MD, PhD, FHRS

Source: Heart Rhythm Volume 12, Issue 4, April 2015, Pages 668–672


Subjects:

Author Supplied Keywords: Atrial fibrillation; MRI; Late gadolinium enhancement; Fibrosis; Catheter ablation

Abstract: The purpose of this study was to define the characteristics of preexisting vs ablation-induced LA LGE. LGE-MRI was prospectively performed before and ≥3 months after initial ablation in 20 patients. The intracardiac locations of ablation points were coregistered with the corresponding sites on axial planes of postablation LGE-MRI. The image intensity ratio (IIR), defined as the LA myocardial MRI signal intensity divided by the mean LA blood pool intensity, and LA myocardial wall thickness were calculated on pre- and postablation images. Imaging data from 409 pairs of pre- and postablation axial LGE-MRI planes and 6961 pairs of pre- and postablation image sectors were analyzed. Ablation-induced LGE revealed a higher IIR, suggesting greater contrast uptake and denser fibrosis, than did preexisting LGE (1.25 ± 0.25 vs 1.14 ± 0.15; P < .001). In addition, ablation-induced LGE regions had thinner LA myocardium (2.10 ± 0.67 mm vs 2.37 ± 0.74 mm;P < .001). Regions with ablation-induced LGE exhibit increased contrast uptake, likely signifying higher scar density, and thinner myocardium as compared with regions with preexisting LGE. Future studies examining the association of postablation LGE intensity and nonuniformity with ablation success are warranted and may inform strategies to optimize ablation outcome.

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Abstract 97

Title: Synergy between surface and core entrapped metals in a mixed manganese–gadolinium nanocolloid affords safer MR imaging of sparse biomarkers

Authors: Kezheng Wang, MD, PhD, Dipanjan Pan, PhD, Anne H. Schmieder, MS, Angana Senpan, PhD, Dennis E. Hourcade, PhD, Christine T.N. Pham, MD, Lynne M. Mitchell, BS, Shelton D. Caruthers, PhD, Grace Cui, MS, Samuel A. Wickline, MD, Baozhong Shen, MD, PhD, Gregory M. Lanza, MD, PhD

Source: Nanomedicine: Nanotechnology, Biology and Medicine Volume 11, Issue 3, April 2015, Pages 601–609


Subjects:

Author Supplied Keywords: MRI; Contrast media; Manganese; Gadolinium; Complement activation; Nanoparticle

Abstract: High-relaxivity T1-weighted (T1w) MR molecular imaging nanoparticles typically present high surface gadolinium payloads that can elicit significant acute complement activation (CA). The objective of this research was to develop a high T1w contrast nanoparticle with improved safety. We report the development, optimization, and characterization of a gadolinium–manganese hybrid nanocolloid (MnOL-Gd NC; 138 ± 10 (Dav)/nm; PDI: 0.06; zeta: − 27 ± 2 mV). High r1 particulate relaxivity with minute additions of Gd-DOTA-lipid conjugate to the MnOL nanocolloid surface achieved an unexpected paramagnetic synergism. This hybrid MnOL-Gd NC provided optimal MR TSE signal intensity at 5 nM/voxel and lower levels consistent with the level expression anticipated for sparse biomarkers, such as neovascular integrins. MnOL NC produced optimal MR TSE signal intensity at 10 nM/voxel concentrations and above. Importantly, MnOL-Gd NC avoided acute CA in vitro and in vivo while retaining minimal transmetallation risk.

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Abstract 98

Title: The prognostic value of gadolinium-enhanced magnetic resonance imaging in acute invasive fungal rhinosinusitis

Authors: Ji Heui Kim, Byung Chul Kang, Jung-Hyun Lee, Yong Ju Jang, Bong-Jae Lee, Yoo-Sam Chung

Source: Journal of Infection Volume 70, Issue 1, January 2015, Pages 88–95


Subjects: LoCE lesions in Gd-enhanced MRI of AIFRS should be early detected. LoCE lesions in Gd-enhanced MRI of AIFRS have to be surgically removed. CE lesions in Gd-enhanced MRI of AIFRS may be treated with antifungal therapy. Remnant LoCE lesions after surgery is associated with unfavorable survival of AIFRS. Hematologic remission and blood sugar are also crucial in the prognosis of AIFRS.

Author Supplied Keywords: Acute invasive fungal rhinosinusitis; Gadolinium; Magnetic resonance imaging

Abstract: This study aimed to assess the prognostic value of gadolinium (Gd)-enhanced magnetic resonance imaging (MRI) in acute invasive fungal rhinosinusitis (AIFRS) and offer recommendations for determining surgical extent based on loss of contrast enhancement (LoCE), which reveals tissue ischemia from fungal invasion. Preoperative and postoperative Gd-enhanced MRI was evaluated in 21 patients with confirmed AIFRS who underwent wide debridement and antifungal therapy. Patients were subdivided by AIFRS-specific survival. LoCE and contrast enhancement (CE) of intrasinonasal and extrasinonasal sites in preoperative and postoperative MRI were compared between the two groups. All patients had preoperative intrasinonasal LoCE and CE lesions, which did not differ between survivors and non-survivors. Bone destruction on CT was detected in 8 of 16 survivors (50%) and 4 of 5 non-survivors (80%). Intrasinonasal LoCE lesions were completely removed by surgery in all cases. Postoperative extrasinonasal LoCE lesions were found in all non-survivors but no survivors (p < 0.001). However, postoperative intrasinonasal and extrasinonasal CE lesions were detected in both survivors and non-survivors (p = 0.119 and p = 0.111, respectively). In addition, remission of hematologic diseases at the time of diagnosis of AIFRS and blood sugar control in diabetic patients were significantly associated with AIFRS-specific survival (p = 0.028 and p = 0.023, respectively). LoCE lesions, which have to be surgically removed, should be screened using Gd-enhanced MRI for an earlier diagnosis of AIFRS, determination of surgical extent, and management of follow-up. Remnant LoCE lesions after surgery, active hematologic diseases, and poorly controlled blood sugar adversely affect the AIFRS-survival.

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Abstract 99

Title: Gadolinium enhancement in newly diagnosed patients with lumbar disc herniations are associated with inflammatory peridiscal tissue reactions

Authors: Mario Löhr, Lydia Lebenheim, Frank Berg, Werner Stenzel, Jürgen Hescheler, Marek Molcanyi, Ralf-Ingo Ernestus, Bert Bosche

Source: Clinical Neurology and Neurosurgery Volume 119, April 2014, Pages 28–34


Subjects:

Author Supplied Keywords: Disc herniation; Lumbar spine; Inflammation; Gadolinium enhancement; Macrophages

Abstract: It is debatable whether a local inflammatory tissue response caused by herniated disc material contributes to sciatic pain and/or sensorimotor deficits. The impact of inflammatory changes on local tissue remodeling, the healing process and the clinical course of disease remains unclear. In this prospective observational study, we included a total of 31 patients with a single-level, unilateral lumbar disc herniation. The diagnosis was confirmed by magnetic resonance imaging (MRI) ± gadolinium. The presence of peridiscal contrast enhancement was correlated with the extent of inflammatory reactions in the herniated fragments as confirmed by immunohistochemistry; clinical symptoms, including the duration of radicular pain; and the incidence of sensorimotor deficits. Peridiscal contrast enhancement was found in 17 patients (55%) and was encasing the adjacent rootlet in 4 cases. There was no significant correlation between gadolinium uptake and the presence of sensorimotor deficits or the duration of radicular symptoms. Degenerative changes were observed in all 31 disc specimens. Overall, 18 cases exhibited increased cellularity in the marginal areas, which were mostly populated by CD68+ macrophages and fibroblasts. Additionally, these areas displayed a limited number of CD3+ T-lymphocytes and different degrees of concomitant neovascularisation, which represented a chronic and unspecific immune response. Peridiscal contrast enhancement on MRI was significantly correlated with the histopathological characteristics of tissue inflammation. However, no correlation was found between the histological evidence and the degree of inflammation and neurological symptoms. Gadolinium-enhanced MRI is a sensitive method to detect unspecific inflammatory reactions in therapy-naïve disc herniations. However, the neuroradiological and histological evidence of peridiscal inflammation was not correlated with the severity of pain or sensorimotor deficits in our patients. Additional research is needed because the occurrence of local inflammation may indicate an ongoing degradation of herniated fragments and thus be helpful in therapeutic decision-making.

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Abstract 100

Title: Three-dimensional segmentation of the left ventricle in late gadolinium enhanced MR images of chronic infarction combining long- and short-axis information

Authors: Dong Wei, Ying Sun, Sim-Heng Ong, Ping Chai, Lynette L. Teo, Adrian F. Low

Source: Medical Image Analysis Volume 17, Issue 6, August 2013, Pages 685–697


Subjects: An automatic 3D segmentation framework for late gadolinium enhanced (LGE) cardiac MRI.

We integrate long-axis images with short-axis images for the 3D segmentation.

A parametric model of the left ventricle for LGE images based on 1D intensity profile.

All images are realigned in 3D to eliminate misalignment artifacts among slices.

Author Supplied Keywords: 3D segmentation; 20 Late gadolinium enhanced cardiac MRI; 21 Pattern intensity; 22 1D intensity profile; 23 Simplex mesh

Abstract: Automatic segmentation of the left ventricle (LV) in late gadolinium enhanced (LGE) cardiac MR (CMR) images is difficult due to the intensity heterogeneity arising from accumulation of contrast agent in infarcted myocardium. In this paper, we present a comprehensive framework for automatic 3D segmentation of the LV in LGE CMR images. Given myocardial contours in cine images as a priori knowledge, the framework initially propagates the a priori segmentation from cine to LGE images via 2D translational registration. Two meshes representing respectively endocardial and epicardial surfaces are then constructed with the propagated contours. After construction, the two meshes are deformed towards the myocardial edge points detected in both short-axis and long-axis LGE images in a unified 3D coordinate system. Taking into account the intensity characteristics of the LV in LGE images, we propose a novel parametric model of the LV for consistent myocardial edge points detection regardless of pathological status of the myocardium (infarcted or healthy) and of the type of the LGE images (short-axis or long-axis). We have evaluated the proposed framework with 21 sets of real patient and four sets of simulated phantom data. Both distance- and region-based performance metrics confirm the observation that the framework can generate accurate and reliable results for myocardial segmentation of LGE images. We have also tested the robustness of the framework with respect to varied a priori segmentation in both practical and simulated settings. Experimental results show that the proposed framework can greatly compensate variations in the given a priori knowledge and consistently produce accurate segmentations.

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gadolinium in mri analysis

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