MAPPING OF BIREFRINGENCE AND THERMAL-DAMAGE IN TISSUE BY USE OF POLARIZATION-SENSITIVE OPTICAL COHERENCE TOMOGRAPHY

We demonstrate cross-sectional birefringence- and polarization-indepen dent backscatter imaging of laser-induced thermal damage in porcine my ocardium in vitro, using a polarization-sensitive optical coherence to mography system. We compare the generated images with histological sec tions of the tissue and demonstrate that birefringence is a more sensi tive indicator of thermal damage than is backscattered Light. Loss of birefringence in thermally damaged regions is quantified and shown to have significant contrast with undamaged sections of the tissue. A det ailed theoretical analysis of the birefringence measurements is provid ed, including a calculation of the systematic errors associated with b ackground noise, system imperfections, and tissue dichroism. (C) 1998 Optical Society of America.