Optical Characterization of Biological Tissues in Visible and Near-Infrared Spectra

Abstract

The rapid development and continuous progress of optical imaging in the medical field require a profound knowledge of the biological tissue's optical signature. Toward this goal, an investigation for different biological soft tissues is performed to capture their optical signatures. These signatures were captured using an imaging spectrometer. The imaging spectrometer encompasses a hyperspectral camera operating in the range of 380 to 1050 nm. The former range is used; to capture the tissue's light transmission (T <inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">r</inf> ) and diffuse reflectance (R <inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">d</inf> ), respectively. Two exploratories (Transmission / Reflection) arrangements were used to study three biological organs: kidney, heart, and liver. In this study, 30 samples were optically investigated in the visible and near-infrared (VIS-NIR) spectrum. To recognize the ideal wavelength, we utilized oneway variance analysis, followed by a Tukey's test for the generated groups (Kidney vs Heart: group#1 / Kidney vs Liver: group#2 / Heart vs Liver: group#3). The optimal spectral range of the measured light T <inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">r</inf> was 640~680 nm for the three groups. Although, the ideal spectral range for the measured light R <inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">d</inf> was 720~760 nm for both group#1 and group#2. On the other hand, group #3 result was dissimilar 520~560 nm. The presented investigation provides a characterization of the biological soft tissues (kidney, liver, and heart) regarding their optical properties to help in the oncology diagnostic and therapeutic techniques.