Monte Carlo Model for Describing Photon Interactions with Biological Tissue in New Approaches of Polarization-Sensitive Optical Coherence Tomography

This work presents results from using a Monte Carlo model to describe photon interactions with a scattering and absorbing medium, exemplified by the eye cornea in polarization-sensitive optical coherence tomography (PS-OCT) approaches. The interaction of an incident photon packet with a weakly scattering birefringent object was analyzed using the meridian plane Monte Carlo approach, which made it possible to take into account the depolarization of radiation during interaction with the scattering centers of the eye corneal epithelium and to increase the signal-to-noise ratio of object information. The dynamic and geometric phase reconstruction in a modified Mach-Zehnder interferometer scheme allows to obtain data of collagen fibers orientation non-invasive, to restore lost information of the birefringent object structure. The result of this reconstruction is a complete picture of the stromal structure with an accuracy that surpasses current levels achieved with existing PS-OCT systems.