Optical Coherence Tomography Angiography Assessment of the Peripapillary Vessel Density and Structure in Patients with Nonarteritic Anterior Ischemic Optic Neuropathy: A Meta-Analysis

Abstract

Background. This meta-analysis is aimed at assessing the peripapillary vessel density (VD) and structural outcomes using optical coherence tomography angiography (OCTA) in patients with nonarteritic anterior ischemic optic neuropathy (NAION). Methods. A comprehensive search of PubMed, Embase, Cochrane Library, and Web of Science databases for literature comparing VD and structural outcomes in patients with NAION and controls was performed. Mean differences (MDs) and its 95% confidence interval (CI) were calculated for continuous estimates. Review Manager (V5.30) was used for analysis. Results. Fourteen published studies met the requirement. The radial peripapillary capillary (RPC) whole enface VD measured by OCTA was significantly lower in patients with NAION compared to that of the controls ( $\text{MD}=-10.51$ , $P<0.00001$ ). The RPC inside disc VD was significantly decreased in the NAION group than that in the control group ( $\text{MD}=-8.47$ , $P<0.00001$ ). For RPC peripapillary VD, there was a statistically significant difference between patients with NAION and the controls ( $\text{MD}=-12.48$ , $P<0.00001$ ). The peripapillary retinal nerve fibre layer (p-RNFL) thickness was significantly lower in patients with NAION in comparison to the controls ( $\text{MD}=-22.18$ , $P=0.004$ ). The ganglion cell complex (GCC) thickness in the macular zone of NAION patients was remarkably reduced compared to that in the controls ( $\text{MD}=-17.18$ , $P=0.0002$ ). Conclusions. The findings suggested that the peripapillary VD and RNFL thickness were attenuated, and the macular GCC thickness was reduced in patients with NAION. OCTA, in the future, may facilitate the diagnosis and monitoring of patients with NAION.