A diffuse reflectance spectral imaging system for tumor margin assessment using custom annular photodiode arrays.


Diffuse reflectance spectroscopy (DRS) is a well-established method to quantitatively distinguish between benign and cancerous tissue for tumor margin assessment. Current multipixel DRS margin assessment tools are bulky fiber-based probes that have limited scalability. Reported herein is a new approach to multipixel DRS probe design, which utilizes direct detection of the DRS signal by using optimized custom photodetectors in direct contact with the tissue. This first fiberless DRS imaging system for tumor margin assessment consists of a 4 × 4 array of annular silicon photodetectors and a constrained free-space light delivery tube optimized to deliver light across a 256 mm(2) imaging area. This system has 4.5 mm spatial resolution. The signal-to-noise ratio measured for normal and malignant breast tissue-mimicking phantoms was 35 dB to 45 dB for λ = 470 nm to 600 nm.





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Publication Info

Dhar, Sulochana, Justin Y Lo, Gregory M Palmer, Martin A Brooke, Brandon S Nichols, Bing Yu, Nirmala Ramanujam, Nan M Jokerst, et al. (2012). A diffuse reflectance spectral imaging system for tumor margin assessment using custom annular photodiode arrays. Biomedical optics express, 3(12). pp. 3211–3222. 10.1364/boe.3.003211 Retrieved from https://hdl.handle.net/10161/22464.

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Gregory M. Palmer

Professor of Radiation Oncology

Greg Palmer obtained his B.S. in Biomedical Engineering from Marquette University in 2000, after which he obtained his Ph.D. in BME from the University of Wisconsin, Madison. He is currently an Associate Professor in the Department of Radiation Oncology, Cancer Biology Division at Duke University Medical Center. His primary research focus has been identifying and exploiting the changes in absorption, scattering, and fluorescence properties of tissue associated with cancer progression and therapeutic response. To this end he has implemented a model-based approach for extracting absorber and scatterer properties from diffuse reflectance and fluorescence measurements. More recently he has developed quantitative imaging methodologies for intravital microscopy to characterize tumor functional and molecular response to radiation and chemotherapy. His awards have included the Jack Fowler Award from the Radiation Research Society.

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Martin A. Brooke

Associate Professor of Electrical and Computer Engineering

Martin A. Brooke received the B.E. (Elect.) Degree (1st. Class Hons.) from Auckland University in New Zealand in 1981. He received the M.S. and Ph. D. in Electrical Engineering from The University of Southern California in 1984, and 1988, respectively. He is currently an Associate Professor of Electrical Engineering at Duke University. Professor Brooke was an Analog Devices Career development award recipient from 1988-1993, won a National Science Foundation Research Initiation Award in 1990, the 1992 IEEE Midwest Symposium on Circuits and Systems, Myril B. Reed Best Paper Award, and the Georgia Tech Outstanding Thesis Advisor Award in 2003. He has graduated twenty three PhD students from his research group and has eight U.S. patents awarded. He has published more than 160 articles in technical Journals and Proceedings, and articles on his work have appeared in several trade and news publications. Dr. Brooke is a senior member of the IEEE.


Nan Marie Jokerst

J. A. Jones Distinguished Professor of Electrical and Computer Engineering

Dr. Nan Marie Jokerst is the J. A. Jones Distinguished Professor of Electrical and Computer Engineering at Duke University, and the Executive Director of the Duke Shared Materials Instrumentation Facility, a Duke shared cleanroom and characterization facility. She received her BS in Physics from Creighton University in 1982, and her MS and PhD in Electrical Engineering from the University of Southern California in 1984 and 1989, respectively. She is a Fellow of the IEEE, and has served as an elected member of the IEEE LEOS Board of Governors, and as the VP for Conferences and as the VP Technical Affairs. She is a Fellow of the Optical Society of America, and has served as Chair of the OSA Engineering Council. Her awards include an NSF Presidential Young Investigator Award, an IEEE Third Millenium Medal, the IEEE/HP Harriet B. Rigas Medal, and the Alumni in Academia Award for the University of Southern California Viterbi School of Engineering. She currently serves on the National Academies Board on Global Science and Technology. She has published over 200 refereed journal and conference publications, and has 6 patents.

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