Noninvasive imaging of biological tissues using optical reflectance system
18 Mar 2016-pp 1-6
TL;DR: In this paper, the authors proposed reflectance systems consisting of a scanning probe with four units, each unit equipped with a photon injection port, and these ports are arranged in a straight line fashion to collect the backscattered photons from different depths.
Abstract: The noninvasive detection of inhomogeneities in biological tissues is studies using phantoms. The proposed reflectance systems consist of a scanning probe with four units. Each unit equipped with a photon injection port, and these ports are arranged in a straight line fashion to collect the backscattered photons from different depths. The inhomogeneities are placed in three different depths like 7mm, 12mm, and 17mm respectively. Through source ports light is superimposed on tissue phantom and collect the backscattered light from various depth. Red and Infrared light emitting diodes with a wavelength of 660nm and 940nm is used in the system. Twelve photodetectors are arranged in four layers with three in each. In order to obtain more information about inhomogeneities, the distance between source and detector also varies (7mm, 12mm, and 17mm). The data obtained from two different wavelength gives exact information about the location of inhomogeneities. By using the method, it is possible to detect inhomogeneities in the early stages of cancer. The advantages are time taken for scanning a given area is lower, easy to locate inhomogeneties, user-friendly, the cost of the system is less.
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TL;DR: A review of reported tissue optical properties summarizes the wavelength-dependent behavior of scattering and absorption in cells and tissues.
Abstract: A review of reported tissue optical properties summarizes the wavelength-dependent behavior of scattering and absorption. Formulae are presented for generating the optical properties of a generic tissue with variable amounts of absorbing chromophores (blood, water, melanin, fat, yellow pigments) and a variable balance between small-scale scatterers and large-scale scatterers in the ultrastructures of cells and tissues.
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TL;DR: Finite mesh-based numerical methods are introduced to calculate the diffuse light field in complex tissues with arbitrary boundaries and applications in tissue spectroscopy and imaging illustrate these theoretical and computational tools.
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