Polarization-sensitive Fourier domain optical coherence tomography for the imaging the anterior segment disorder of the eyes

摘要

Polarization properties of anterior segment disorders of the eyes were evaluated using a fiber-based polarization-sensitive Fourier-domain optical coherence tomography (PS-FD-OCT). The light source is a superluminescent diode with a central wavelength of 840 nm, and bandwidth of 50 nm. Synchronized two line-CCD cameras allow high-speed measurement of birefringence of retina (line rate 27.7 kHz), and the sensitivity of the system is 100.7 dB. Birefringence of the optical fiber was compensated with the surface reflection. Phase retardation and orientation of the birefringence were measured with a Jones matrix based algorithm. The phase retardation map of the anterior segment was visualized as a depth-resolved three-dimensional image in addition to the conventional cross sectional OCT image. In the polarization image of the normal eye, striking polarization change was observed at the sclera. In the eyes with necrotizing scleritis, abnormal thinning of the sclera could be confirmed. In the eyes after filtering glaucoma surgery, polarization change in the conjunctiva due to the abnormal fibrosis after surgery could be observed. PS-FD-OCT is an effective tool to understand the polarization properties of different types of pathological changes in the anterior segment of the eye.