Evaluation of retinal vascular changes has been substantially improved in recent years by the introduction of optical coherence tomography angiography (OCT-A). Can the same be said for glaucoma care? Compared with current imaging methods, it remains unclear. To clear up some of this ambiguity, a team of Portuguese and French researchers performed a systematic review and meta-analysis of studies investigating vessel density (VD) in glaucoma patients using OCT-A.

The team conducted a literature search on various sites and a manual search to find prospective studies that used OCT-A to compare the VD in glaucomatous eyes with the VD in healthy control eyes. Of 3,045 articles, 24 were included in the broad characterization and 18 in the meta-analysis.

The researchers observed a statistically significant reduction in the mean peripapillary VD (MPVD), the mean whole optic nerve image VD, the mean inside-disc VD and the mean parafoveal VD in 888 glaucomatous eyes compared with 475 healthy control eyes. Their subgroup analyses revealed a significant difference in the MPVD across glaucoma subtypes and OCT-A devices.

These findings suggest there is a diagnostic utility of using OCT-A to detect glaucomatous eyes; however, further longitudinal prospective studies are needed to characterize vascular changes in glaucoma patients.