Comprehensive Investigation of the Eye-Cornea Structure Based on the Extended Techniques of Polarization-Sensitive Optical Coherence Tomography.

Abstract

We present a universal technique for noninvasive investigation of thin multilayer optically transparent tissues based on polarization-sensitive optical coherence tomography. To reach higher diagnostic accuracy, we revisit the model of the cornea structure and reconsider the physical features of the interaction of light with the tissue structural elements. In the scheme proposed, the probing beam is algorithmically adjustable such that the x-polarized radiation impinges each consecutive structural layer; the object beam is formed by the reflection and back-scattering. Its characteristics are found analytically and numerically within the framework of the polarized Monte-Carlo model and the Jones matrix formalism. A modified Mach-Zehnder interferometer with orthogonal polarization channels enables the elimination of the object-signal depolarization caused by stochastic scattering and facilitates evaluation of the refractive indices and birefringence of tissue elements. The technique permits spatial scanning of the object, providing a complete 3D mapping with a submicrometer resolution in the longitudinal and transverse directions.