Plexus-specific retinal capillary avascular area in exudative age-related macular degeneration with projection-resolved OCT angiography

Objective To detect the plexus-specific retinal capillary avascular area in exudative age-related macular degeneration (EAMD) with projection-resolved optical coherence tomography angiography (PR-OCTA). Methods and analysis In this prospective cross-sectional single centre study, eyes with treatment-naive EAMD underwent macular 3x3 mm OCTA with AngioVue system. OCTA scans were analysed and processed including three-dimensional projection artefact removal, retinal layer semi-automated segmentation and en face angiogram generation. Automated quantification of extrafoveal (excluding the central 1 mm circle) avascular area (EAA) were calculated on projection-resolved superficial vascular complex (SVC), intermediate capillary plexus (ICP) and deep capillary plexus (DCP), respectively. Results Nineteen eyes with EAMD and 19 age-matched healthy control eyes were included. There was no significant difference between the EAMD and control eyes in terms of age, sex, axial length and mean ocular perfusion pressure (all p>0.05). Compared with control eyes, EAMD eyes had significantly larger EAA in SVC (median 0.125 vs 0.059 mm(2), p=0.006), ICP (0.016 vs 0.000 mm(2), p=0.004) and DCP (0.033 vs 0.000 mm2, p<0.001). Conclusion PR-OCTA showed that EAMD is associated with focal avascular area in all the three retinal vascular plexuses.

Automated summary

PR-OCTA can detect the plexus-specific retinal capillary avascular area in patients with EAMD. The study found that EAMD patients had significantly larger avascular areas in the superficial, intermediate, and deep capillary plexuses compared to the healthy control group.