High-definition imaging of retinal lesions in age related macular degeneration by polarization sensitive OCT with retinal tracking

Abstract

 

Purpose

 

To demonstrate the functionality of a new polarization sensitive (PS) OCT system with an integrated retinal tracker to record images of retinal lesions with tissue specific contrast in eyes affected by age related macular degeneration (AMD).

 

Methods

 

A new fiber optic high-speed PS-OCT system equipped with a hardware retinal tracker was developed. An integrated SLO channel operating at 60 Hz frame rate provides information on ocular motion. The SLO data are used to provide a real-time correction of motion artifacts for the PS-OCT sub-system. The PS-OCT system acquires tomographic images at 70 kHz A-scan rate up to 28° x 21° field of view. A 1024 x 256 scan 3D volume is recorded in 4.6 sec. Intensity, retardation, optic axis orientation, and depolarization images are recorded simultaneously. 30 eyes of patients with age-related macular degeneration were imaged. 3D data sets and high-definition, multiply averaged cross sectional images were recorded in eyes affected with various forms of AMD (drusen, geographic atrophies, CNV).

 

Results

 

The tracker enables recording of averaged, noise reduced 2D images and of 3D data sets free of motion distortions. Drusen and geographic atrophies can be clearly delineated by segmenting the adjacent RPE based on its depolarizing properties. Scars associated with neovascular AMD could be clearly identified by the birefringence generated by the ordered collagen fibers.

 

Conclusions

 

PS-OCT with retinal tracking provides tissue specific contrast with improved image quality.

 

Keywords: 552 imaging methods (CT, FA, ICG, MRI, OCT, RTA, SLO, ultrasound) • 412 age-related macular degeneration • 701 retinal pigment epithelium