Optical coherence tomography imaging for glaucoma-today and tomorrow

Abstract

Digital imaging technologies for glaucoma diagnostics have evolved rapidly over the recent years. From time-domain optical coherence tomography (OCT) to spectral-domain and swept-source OCTs, the application of OCT for analysis of the anterior chamber angle and the optic nerve head (ONH) is expanding. The second-generation anterior segment swept-source OCT is able to image the configuration of the anterior chamber angle in 3 dimensions in less than 1 second and perform 360-degree analysis of the anterior chamber angle width for detection of angle closure. The morphology, density, and dimensions of the crystalline lens in relation to the anterior chamber can now be examined from the anterior corneal surface to the posterior lens surface, facilitating the investigation of the involvement of the crystalline lens in primary angle closure. Spectral-domain and swept-source OCTs have improved the measurement reliability of the lamina cribrosa and the neuroretinal rim configurations. Studying the deformation of the lamina cribrosa and ONH surfaces is relevant to decipher the mechanisms of ONH damage in the development and progression of glaucoma. Software and algorithms for automatic analysis of the anterior chamber angle dimensions and deformation of the ONH and lamina cribrosa surfaces are required to process large volumetric data sets, and they are under active development. It is expected that new imaging technologies will improve the detection and risk assessment of angle-closure and open-angle glaucomas.