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Electrical Impedance Tomography with Tomosynthesis for Breast Cancer Detection

Jonathan Newell

Electrical Impedance Tomography with Tomosynthesis for Breast Cancer Detection

Jonathan Newell

Rensselaer Polytechnic Institute

With:David Isaacson Gary J. Saulnier

Tzu-Jen Kao Greg Boverman Richard Moore* Daniel Kopans*

And: Rujuta Kulkarni Chandana TammaDavid Ardrey Neha Pol

*Massachusetts General Hospital

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EIT electrodes added to mammography machine.EIT electrodes added to mammography machine.

1 : 2 : 4 : 2 : 1 is the ratio of the mesh thicknesses. Only the center layer, III, is displayed in the results.

1 : 2 : 4 : 2 : 1 is the ratio of the mesh thicknesses. Only the center layer, III, is displayed in the results.

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EIT InstrumentationEIT Instrumentation

ACT 4 with Tomosynthesis unit Radiolucent electrode array

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Co-registration of EIT and Tomo Images Co-registration of EIT and Tomo Images

To find the electrode position, display the slice containing the electrodes. Superimpose the mesh grid with correct scale.

Slice 15 of 91

Then select the desired tomosynthesis layer.

Slice 50 of 91

HS_14RNormal

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Admittance Loci: format for summaries of EIS dataAdmittance Loci: format for summaries of EIS data

Results of in-vitro studies of excised breast tissue. Jossinet & Schmitt 1999

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120 EIS plots for a normal breast (HS14_Right)120 EIS plots for a normal breast (HS14_Right)

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HS25_L: Invasive Ductal CarcinomaHS25_L: Invasive Ductal Carcinoma

ROI 1

ROI 2

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Linear Correlation Measure –LCMLinear Correlation Measure –LCM

0

1

2

3

4

5

0 1 2 3 4 5 6

0

1

2

3

4

5

0 1 2 3 4 5 6

Y

Ym

compute for

each voxel

LCM Image 700

0

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LCM Image of invasive ductal CA (HS25_L)LCM Image of invasive ductal CA (HS25_L)

Gray scale image of LCM

700

0

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HS21_R: Fibroadenoma in the upper boxHS21_R: Fibroadenoma in the upper boxROI 1

ROI 2

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LCM Image of fibroadenoma (HS21_R)LCM Image of fibroadenoma (HS21_R)

Gray scale image of LCM

350

0

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HS10_L: Invasive Ductal CA“Proliferation is worrisome”HS10_L: Invasive Ductal CA“Proliferation is worrisome”

ROI 1

ROI 2

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LCM Image of invasive ductal CA (HS10_L)LCM Image of invasive ductal CA (HS10_L)

Gray scale image of LCM

1300

0

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LCM for 11 normal breasts LCM for 11 normal breasts

There are 120 EIS plots for layer 3 in each patient. The distribution of the LCM parameter in these plots is shown.

300

0

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LCM for the regions of interest in 4 patientsLCM for the regions of interest in 4 patients

The distributions of the LCM for the regions of interest identified. Note the LCM values are much larger for voxels associated with the malignant lesions.

Hyalinized

Fibroadenoma

Invasive ductal

carcinoma

Normal Normal

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LCM on the same scale for a normal subject, a fibroadenoma and two carcinomasLCM on the same scale for a normal subject, a fibroadenoma and two carcinomas

Normal Breast

Fibroadenoma

Invasive Ductal Carcinoma

Invasive Ductal Carcinoma

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ConclusionsConclusions

We have discovered a quantitative parameter derived from the admittance spectra that is markedly different in malignancy from normal breast tissues.

This parameter is location-specific to the tumor. We need to study more patients with more

benign lesions and tumors in order to evaluate the clinical potential of this parameter to improve the sensitivity and specificity of breast cancer screening.

We will present additional details about our system and its results in four posters at this meeting. See Kao, Boverman, Kulkarni and Tamma.

We have discovered a quantitative parameter derived from the admittance spectra that is markedly different in malignancy from normal breast tissues.

This parameter is location-specific to the tumor. We need to study more patients with more

benign lesions and tumors in order to evaluate the clinical potential of this parameter to improve the sensitivity and specificity of breast cancer screening.

We will present additional details about our system and its results in four posters at this meeting. See Kao, Boverman, Kulkarni and Tamma.

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Clinical details of the four patients.Clinical details of the four patients.

Patient # Pathology report, Grade, EIS spectra and LCM value

HS14_R

Screening patient, normal breast, No biopsy report All EIS plots have good curvature.LCM < 137 for all regions. Maximum value of LCM: 137.

HS21_R

Hyalinized Fibroadenoma, no evidence of malignancyMost EIS Plots have good curvature.LCM < 328 for the tumor region.LCM < 200 for most other regions Maximum value of LCM: 328.

HS25_L

Invasive ductal carcinoma, Ductal carcinoma in-situA few cylindrical to irregular tan-yellow soft tissue cores ranging from 0.3 to 1.2 cm in length and averaging 0.1 cm in diameter.Grade: 3/3 EIS plots on bottom right corner are abnormal. LCM > 400 for the tumor region. Maximum value of LCM: 709.

HS10_L

Invasive ductal carcinoma, (Proliferation is worrisome)Ductal carcinoma in-situAtypical ductal hyperplasiaTumor size: 1..1 x 0.9 x 0.7 cm and two satellite nodules, 0.14 cm and < 0.1 cm.Grade:3/3Most EIS plots are close to a straight line.LCM > 400 for most plots.Maximum value of LCM: 1230.

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Summary of first 38 patients accruedSummary of first 38 patients accrued

Total patient studied: 37-7 = 30 First 7 patients were needed to develop

correct operational procedures. 19 breasts are underwent biopsy 7 of these were reported as CA 4 breasts of these were located outside

of the electrode region. 3 CA breasts are OK for analysis

Total patient studied: 37-7 = 30 First 7 patients were needed to develop

correct operational procedures. 19 breasts are underwent biopsy 7 of these were reported as CA 4 breasts of these were located outside

of the electrode region. 3 CA breasts are OK for analysis

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Threshold for Parameter, Straightness imageThreshold for Parameter, Straightness image

After preliminary study, we can set a threshold for normal or abnormal EIS plot.

400 will be the first guess with these patient data.

The previous image will be show again with full scale set to 700.

After preliminary study, we can set a threshold for normal or abnormal EIS plot.

400 will be the first guess with these patient data.

The previous image will be show again with full scale set to 700.