Diagnosing glaucoma progression with optical coherence tomography

Abstract

Optical coherence tomography (OCT) imaging of the retinal nerve fiber layer (RNFL), optic nerve head (ONH) and macula has gained popularity in recent years to detect and monitor glaucoma. With significant improvement in scan speed and scan resolution, spectral-domain OCT has become an efficient platform to evaluate progressive RNFL thinning and ONH remodeling. This review summarizes the recent progress of OCT RNFL, ONH and macular measurements for the detection of glaucoma progression. The RNFL thickness map facilitates visualization of RNFL defects and their progression patterns, and attains a higher sensitivity to detect glaucoma progression compared with the conventional circumpapillary RNFL thickness profile. The measurement of lamina cribrosa displacement is informative to discern the relationship between intraocular pressure and ONH modeling. Ganglion cell and inner plexiform layer analysis has offered a useful alternative to track glaucoma progression. In the interpretation of progression analysis, the impact of age-related change, disease severity and image signal-to-noise ratio should always be considered. The analyses of the RNFL thickness map, lamina cribrosa displacement and inner macular thickness have provided a new paradigm to evaluate glaucomatous damage and its progression.