We know the choroid contributes to the pathogenesis of AMD. The part retinal perfusion plays, however, is still unclear. Upon further investigation, researchers recently found that retinal vessel density is smaller in eyes with exudative AMD but unaffected by anti-VEGF treatments, suggesting a retinal vascular role in the pathogenesis of AMD.
This retrospective cross-sectional study evaluated 310 eyes of 182 patients with non-exudative (54.2%) or exudative (45.8%) AMD. The team measured retinal vessel density from the superficial capillary plexus in the foveal, parafoveal and full macular regions and foveal avascular zone (FAZ) area, perimeter and circularity. They then compared non-exudative and exudative AMD eyes and analyzed the impact of anti-VEGF treatments and geographic atrophy (GA).
In eyes with AMD, the investigators discovered that vessel density decreased with age in the foveal, parafoveal and full macular regions. Compared with non-exudative AMD eyes, they noted that eyes with exudative AMD had lower vessel density, especially in the parafoveal (29.8±6.3% vs. 33.0±5.7%) and full macular regions (27.9±6.2% vs. 31.2±5.5%). They observed no differences in FAZ area, perimeter or circularity between the two groups. In eyes with exudative AMD, they added that prior anti-VEGF treatments did not impact retinal vascular measurements, while non-exudative AMD severity and central GA impacted retinal vessel density and FAZ morphology.
|Lee SC, Tran S, Amin A, et al. Retinal vessel density in exudative and non-exudative age-related macular degeneration on optical coherence tomography angiography. AM J Ophthalmol. December 16, 2019. [Epub ahead of print].|