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Diffuse Reflectance Spectroscopy: Getting the Capillary Refill Test Under One's Thumb
Published on: December 2, 2017
Assessment of blood supply in superficial tissue by polarization-gated elastic light-scattering spectroscopy
Michael P Siegel1, Young L Kim, Hemant K Roy
1Department of Biomedical Engineering, E310, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208, USA. cgul72@hotmail.com
Abstract:
We report the feasibility of monitoring both hemoglobin oxygen saturation and hemoglobin concentration in the superficial layer of tissue using polarization-gated elastic light-scattering spectroscopy. We detail our analysis technique, the experimental validation of our analysis, and the detection of an early increase in blood supply to the superficial layer of colon tissue in human patients with colonic adenomas as well as in an animal model of colon carcinogenesis. To the best of our knowledge, this study represents the first evidence that polarization gating can be used as a spectroscopic tool to quantify hemoglobin concentration as well as oxygen saturation in the uppermost tissue layer.
