terence cesare

8/6/2019 Terence Cesare

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Doesnt use as primary basis the review of previous publications

Authors say no comparisons of image quality and radiation doses on

craniocervical CTA at 2 different tube currents


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technical advances =computer upgrades/mdct

CT 11% of all radiology US but 2/3 of the collective medical dose.


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different patients with ATCM and FTC due to rad cannot expose pts more

than once. scanning length, maximum transverse neck diameter, and ages

were not significantly different.Eg vascular stenosis or aneurysms not assessed

No comparison of the mean tube currenttime product

NOT estimated the effective dose for ATCM and FTC. CTDI vol and DLP

BMI of the patients may provide better criteria for optimizing


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automatically terminating radiographic exposure in conventional radiography

Benefits of AEC: More uniform image quality (noise)

Reduced dose to less attenuating regions

Reduced load on x-ray tube


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Angular- decrease the selected tube current in projections (in thexyplane)

that cause less attenuation lower mA for AP vs lateral projection.

Z-axis-automatically select a tube current for each slice position in thescanning direction (the z-axis) to maintain a constant image quality.


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SURE Exposure 3D controls and modulates mA in thex, y, and zdirections

to achieve and maintain a uniform user selected noise level in the images.

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More staff needed. Radiologist can be at home to report

Risk of contrast agentinduced nephropathy

Better definition of adjacent bone anatomy

Unenhanced MR angiography can simply be repeated


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Rad dose prop to mAs value when all other factors are held constant.

Rad dose dec = image noise inc. Diagnostic image

DLP provides an indication of the energy imparted to the organs and can beused to assess the overall radiation burden associated with a CT study.


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consecutive= random sample

FTC standard on that CT (median age, 61 years; range, 3290 years; 11

men, 14 women)ATCM (median age, 59 years; range, 1884 years; 10 men, 15 women)

Visipaque 270 - 4 mL/s 40 mL then 3 mL/s 20 mL


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MIP; 8-mm thickness, 2-mm reconstruction interval

VR Advantage Windows, Version 4.2 workstation; GE used. (adw4.2).

ABC ATCM // DEF - FC


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No other information was given. Informed consent or whatever


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Ordinal data can be counted and ordered but not measured.

Values belonging to it can be ranked or have a rating scale.


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Sizes Imp as may affect image quality or dose

2 anatomic levels: the sternocleidomastoid muscle in the upper neck and the

pectoralis major muscle, at shoulder level. ROI (0.51.0 cm2) were placed ina homogeneous region of muscle without fat.


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Blind- no scanning parameters

Where was 5 excellent and 1 poor


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1 Ages, Scanning length, and Maximum transverse neck diameters were not

significantly different

2 No significant difference was detected in image quality3 No sig diff at shoulder but upper neck noise higher with atcm (at shoulder

higher noise that at neck. mA clipped)

3 reduction in radiation dose (18% reduction for both CTDIvol and DLP)

P value greater than 0.05 the same Ho. Lower there is a differnece Hi


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ATCM technique automatically lowered the mA for the neck caused an

increase in objective noise


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Therefore there may still be some room to reduce the radiation dose further

GE a reconstruction engine that sweeps noise from CT images

ASIR algorithm uses statistical noise profiles to ramp image clarity andsuppress noise compared with traditional filtered back-projection (FBP)

techniques.


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terence cesare

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