This K25 award will be used for successful transition for Dr. Mini Das, who is a physicist and optical engineer, to apply her skills to clinically relevant research in breast imaging. Her long-term goals are to be an independent researcher in this area and to develop a research program combining innovative physics with a thorough understanding of relevant biological processes, state of the art imaging techniques and real clinical needs for early stage breast cancer detection. In this proposal, Dr. Das will address some of the existing challenges in transitioning from 2D mammography to 3D breast images. Digital mammography (DM) has shown very high rate of detectability for microcalcifications (MCs), which are the primary precursor for invasive ductal carcinoma (DCIS). While digital breast tomosynthesis (DBT) is a modality waiting for FDA approval, it is not clear if it has been proven good enough to replace DM. Due to the differences in the attenuation properties and size/structure between MCs and masses, it is difficult to optimize DBT systems for best performance for both MC and mass detection from the same reconstructed image In light of these various challenges, the evaluation of the proposed variable dose DBT (VD-DBT) technique proposed here is of high significance. Here, a central projection slice equivalent to DM (primarily for MC detection) and a 3D reconstruction image (primarily for mass detection) can be acquired simultaneously. This method will also provide a smooth transition for the radiologists to obtain both a mammographic image and a 3D reconstructed image simultaneously with the lowest possible total dose. The second part of our proposal to investigate a penalised maximum likelihood (PML) reconstruction method with adjustable priors that can enable low noise image with improved SNR and edge preserving effects can improve the detection of masses using the 3D reconstructed image. This is also highly significant considering the need to reduce the total imaging dose in any proposed breast screening modality like DBT.

National Institute of Health (NIH)
National Cancer Institute (NCI)
Mentored Quantitative Research Career Development Award (K25)
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Subcommittee G - Education (NCI)
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Jakowlew, Sonia B
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University of Houston
Schools of Arts and Sciences
United States
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Gifford, Howard C; Liang, Zhihua; Das, Mini (2016) Visual-search observers for assessing tomographic x-ray image quality. Med Phys 43:1563-75
Das, Mini; Liang, Zhihua (2014) Spectral x-ray phase contrast imaging for single-shot retrieval of absorption, phase, and differential-phase imagery. Opt Lett 39:6343-6
Das, Mini; Liang, Zhihua (2014) Approximated transport-of-intensity equation for coded-aperture x-ray phase-contrast imaging. Opt Lett 39:5395-8
O'Connor, J Michael; Das, Mini; Dider, Clay S et al. (2013) Generation of voxelized breast phantoms from surgical mastectomy specimens. Med Phys 40:041915
Lau, Beverly A; Das, Mini; Gifford, Howard C (2013) Towards Visual-Search Model Observers for Mass Detection in Breast Tomosynthesis. Proc SPIE Int Soc Opt Eng 8668:
Gursoy, Doga; Das, Mini (2013) Single-step absorption and phase retrieval with polychromatic x rays using a spectral detector. Opt Lett 38:1461-3
Das, Mini; Gifford, Howard C; O'Connor, J Michael et al. (2011) Penalized maximum likelihood reconstruction for improved microcalcification detection in breast tomosynthesis. IEEE Trans Med Imaging 30:904-14
Das, Mini; Gifford, Howard C; O'Connor, J Michael et al. (2010) Improved Microcalcification Detection for Breast Tomosynthesis Using a Penalized-Maximum-Likelihood Reconstruction Method. Lect Notes Comput Sci 6136:697-703
O'Connor, J Michael; Das, Mini; Didier, Clay et al. (2010) Development of an Ensemble of Digital Breast Object Models. Lect Notes Comput Sci 6136:54-61
Das, Mini; Gifford, Howard C; O'Connor, J Michael et al. (2009) Evaluation of a variable dose acquisition technique for microcalcification and mass detection in digital breast tomosynthesis. Med Phys 36:1976-84