Detailed Visualization of the Anterior Segment Using Fourier-Domain Optical Coherence Tomography

Abstract

Visualization of the trabecular meshwork and Schlemm’s canal could be a valuable tool for glaucoma diagnosis and treatment, but it requires resolution in the range of tens of micrometers. Optical coherence tomography (OCT) is an emerging noncontact, noninvasive imaging modality for cross-sectional imaging of biological tissue.¹ A time-domain (TD) OCT system operating at a wavelength of 1310 nm and a line rate of 2 kHz has been commercialized for ocular anterior segment imaging (Visante OCT; Carl Zeiss Meditec, Dublin, California). Narrow anterior chamber angles have been studied using a prototype TDOCT imaging system.^2,3 Optical coherence tomography was found to be a promising method for screening individuals at risk for narrow-angle glaucoma, providing higher resolution than ultrasound biomicroscopy with the additional advantages of a noncontact imaging modality compatible with slitlamp biomicroscopy observation. However, Schlemm’s canal and the trabecular meshwork have not been readily visualized with the existing TDOCT systems.⁴