Three-dimensional time-resolved optical mammography of the uncompressed breast

Department of Medical Physics and Bioengineering, University College London, London, WC1E 6BT, UK.
Applied Optics (Impact Factor: 1.78). 07/2007; 46(17):3628-38. DOI: 10.1364/AO.46.003628
Source: PubMed


Optical tomography is being developed as a means of detecting and specifying disease in the adult female breast. We present a series of clinical three-dimensional optical images obtained with a 32-channel time-resolved system and a liquid-coupled interface. Patients place their breasts in a hemispherical cup to which sources and detectors are coupled, and the remaining space is filled with a highly scattering fluid. A cohort of 38 patients has been scanned, with a variety of benign and malignant lesions. Images show that hypervascularization associated with tumors provides very high contrast due to increased absorption by hemoglobin. Only half of the fibroadenomas scanned could be observed, but of those that could be detected, all but one revealed an apparent increase in blood volume and a decrease in scatter and oxygen saturation.

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    • "Optical imaging has been predicted to improve sensitivity and specificity in dense breast tissues, but this has not yet been well established. Most published optical studies focusing on lesion detection and characterization were performed in heterogeneous breast density populations [15-21]. Increased hemoglobin and water content, as well as decreased lipid content were observed in tumors compared to normal surrounding breast tissue. "
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    • "Many groups have reported high total hemoglobin concentration in malignant tumors as compared to normal tissues - an expectable contrasting mechanism due to the sustained angiogenesis occurring in tumors [3,11,12]. Despite of unapparent manifestation in hemoglobin-DOT, some groups have observed a decrease of the oxygen saturation (StO2) in the tumor regions [12–14]. In addition, some researchers have described tumor-to-normal contrast in tissue scattering parameter, ascribed to morphologic changes at a cellular level as well as changes in size and density of subcellular organelles in tumors [15,16]. "
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    • "For both the forward model computation and reconstruction, the imaging domain was discretized into a uniform grid having a spatial resolution of 0.25 cm in the plane and 0.1875 cm along the coordinate. The bulk opitcal parameters were set to cm and cm for both the breast and the outside region in the box, which can be physically realized by filling the box with intralipid that has optical characteristics close to breast tissue [46]. The measurements were generated with a spherical heterogeneity of radius 1 cm present at the position with the coordinate (5,8,3) cm. "
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