Abstract
Purpose :
To investigate the polarizing properties of corneas following deep anterior lamellar keratoplasty.
Methods :
In this study, 20 patients were imaged using our custom-built ultrahigh resolution polarization sensitive optical coherence tomography (PS-OCT). A near limbal-to-limbal imaging field with uniform signal strength throughout the cornea was achieved using a conical scan setup. Cross sections (B-Scans) and enface maps of the cornea at various locations and depths were derived from the polarization sensitive information to observe localized changes in phase retardation (PR) and depolarization.
Results :
PS-OCT provided an improved image contrast (Figure 1b) that can potentially assist in better diagnosis compared to the conventional intensity image (Figure 1a). Since tissue birefringence originated from alignment of collagen fibrils in the stroma, PR information showed strong birefringence at the graft-host interface (see Figure), indicating the microstructural alteration of collagen in those regions. Further, scar morphology and rupturing can also be precisely studied with using PR as a surrogate for wound healing.
Conclusions :
PS-OCT can enable visualization of the alteration of tissue properties following corneal transplant and may reveal unique structural changes prior to graft failure.
This abstract was presented at the 2022 ARVO Annual Meeting, held in Denver, CO, May 1-4, 2022, and virtually.