We propose to build an endoscopic all-fiber clinical device for polarized reflectance spectroscopy based on polarization-maintaining (PM) fiber. We present an instrument for selective detection of scattering characteristics of epithelium and stroma. This method is based on polarized illumination and polarization sensitive detection of scattered light.
Methods of polarized reflectance spectroscopy combine two creative ideas: polarization gating and elastic scattering spectroscopy.
– Polarization gating is based on the difference in microdepolarization of light in epithelian cells, cancer cells and stroma. A collagen fibers can strongly depolarize radiation, cells depolarize more less than fibers. Polarization gating allow to discriminate light originating from epithelium and eliminating the strong diffusive background originating from stroma.
– Elastic scattering spectroscopy is based on dependance of scattering spectrum on cytoplasmic ratio. The scattered spectrum depends on different properties of epithelian nuclei such as diameter distribution, relative refractive index, e.t.c. Therefore, by analyzing experimental spectra and solving the inverse problem one can extract certain parameters of cells, for example, cytoplasmic ratio, which provide direct quantitative diagnostic information. The device is gold medal of the belgian and international trade fair for technological innovation.
1. Mjakov A.V., Agrba P.D., Shakhova N.M., and Kamensky V.A. Polarization optical reflectometry: the technique for puncture diagnosis. Fifth International Conference on Photonics and Imaging in Biology and Medicine (Qingming Luo, Lihong V. Wang, Valery V. Tuchin, Min Gu, eds.). Proc, SPIE, 6534, 653438 (2007).