Simulation and algorithm for photothermal imaging of tissue oxygen saturation

摘要

This study aims to develop a minimal invasive photothermal imaging method to determine the oxygenation level of an internal tissue. In this method, the tissue is illuminated using an optical fiber by several wavelengths in the visible and the near IR range. The absorption of the illuminated radiation causes an increase in the tissue's temperature which is observed by a thermal camera through a coherent waveguide bundle in the mid-IR range. Analyzing the temperature rise allows estimating the tissue composition in general, and specifically the oxygenation level. This system will enable to measure the saturation on superficial tissues as well as within body cavities through a commercial endoscope.rnA theoretical model of this problem was implemented to help design the experimental setup and develop the experimental procedures. A curve-fitting algorithm is used to find the most suitable saturation value affecting the temperature function. The estimated saturation was calculated on different simulated model parameters and was in good agreement with the simulated saturation value.