We report our continued study of phase-contrast diffuse optical tomography (PCCDOT) for evaluating its
fidelity in distinguishing malignant breast lesions form benign ones. 144 breast masses were examined
from 134 patients, aging from 22~82 with the mean age of 56. Tissue optical parameters including
refractive index, and absorption and scattering coefficients, were obtained and compared with their
corresponding biopsy/pathology reports. In consistent with our previous study, malignant masses tended to
have a decreased refractive index relative to their surrounding normal tissue, which acts as the key
character to differentiate them from benign masses. The results show that the specificity is improved
significantly over the previous smaller scale study (85% vs. 70%) due to the addition of significantly more
benign cases, while the sensitivity stays about the same (81% vs. 82%) due to the similar number of
malignant cases used compared to the smaller scale study.
Multispectral and phase-contrast diffuse optical tomography are used to track treatment progress in a patient with locally
advanced invasive carcinoma of the breast cancer during neoadjuvant chemotherapy. Two types of chemotherapy
treatment including four cycles of Adriamycin/Cytoxin (AC cycles) and twelve cycles of Taxol/Herceptin (TH cycles)
were applied to patient. A total of eight optical exams were performed before and within the chemotherapy. Images of
tissue refractive index, and absorption and scattering coefficients, as well as oxy-hemoglobin and deoxy-hemoglobin
concentrations along with scattering particle volume fraction and mean diameter of cellular components were all
obtained. The tumor was identified through absorption and scattering images. Tumor shrinkage was observed during the
course of chemotherapy from all the optical images. Our results show that oxy-hemoglobin, deoxy-hemoglobin and total
hemoglobin in tumor decreased after chemotherapy compared to that of before chemotherapy. Significant changes in
tumor refractive index along with tumor cellular morphology during the entire chemotherapy are also observed.
An automated procedure for detecting breast cancer using near-infrared (NIR) tomographic images is presented. This classification procedure automatically extracts attributes from three imaging parameters obtained by an NIR imaging system. These parameters include tissue absorption and reduced scattering coefficients, as well as a tissue refractive index obtained by a phase-contrast-based reconstruction approach. A support vector machine (SVM) classifier is utilized to distinguish the malignant from the benign lesions using the automatically extracted attributes. The classification results of in vivo tomographic images from 35 breast masses using absorption, scattering, and refractive index attributes demonstrate high sensitivity, specificity, and overall accuracy of 81.8%, 91.7%, and 88.6% respectively, while the classification sensitivity, specificity, and overall accuracy are 63.6%, 83.3%, and 77.1%, respectively, when only the absorption and scattering attributes are used. Furthermore, the automated classification procedure provides significantly improved specificity and overall accuracy for breast cancer detection compared to those by an experienced technician through visual examination.
In this report, a phase-contrast diffuse optical tomography system, which can measure the refractive indices
of human breast masses in vivo, is described. To investigate the utility of phase-contrast diffuse optical
tomography (PCDOT) for differentiation of malignant and benign breast masses in humans, and to compare
PCDOT with conventional diffuse optical tomography (DOT) for analysis of breast masses in humans. 35
breast masses were imaged in 33 patients (mean age = 51 years; range 22-80 years) using PCDOT. Images
characterizing the tissue refractive index, absorption and scattering of breast masses were obtained with a
finite element-based reconstruction algorithm. The accuracies of absorption and scattering images were
compared with images of refractive index in light of the pathology results. Absorption and scattering images
were unable to accurately discriminate benign from malignant lesions. Malignant lesions tended to have
decreased refractive index allowing them to discriminate from benign lesions in most cases. The sensitivity,
specificity, false positive value, and overall accuracy for refractive index were 81.8%, 70.8%, 29.2%, and
74.3%, respectively. Overall we show that benign and malignant breast masses in humans demonstrate
different refractive index and differences in refractive index properties can be used to discriminate benign
from malignant masses in patients with high accuracy. This opens up a new avenue for improved breast
cancer detection using NIR diffusing light.
Access to the requested content is limited to institutions that have purchased or subscribe to SPIE eBooks.
You are receiving this notice because your organization may not have SPIE eBooks access.*
*Shibboleth/Open Athens users─please
sign in
to access your institution's subscriptions.
To obtain this item, you may purchase the complete book in print or electronic format on
SPIE.org.
INSTITUTIONAL Select your institution to access the SPIE Digital Library.
PERSONAL Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.