Optical Coherence Tomography Angiography in Retinal Vein Occlusion: Correlation between Foveal Avascular Zone Area and Visual Acuity

Abstract

Purpose:\xa0\xa0To find out correlation between visual acuity and deep capillary plexus (DCP) in foveal avascular zone (FAZ) area using OCTA in patients with retinal vein occlusion (RVO). \nStudy Design:\xa0\xa0Descriptive observational study. \nPlace and Duration of Study:\xa0\xa0Layton Rehmatullah Benevolent trust free Eye Hospital, from September 2018 to December 2019. \nMethods:\xa0\xa0This observational study included 50 eyes of 50 patients, who were treated with intra-vitreal anti-VEGF for macular edema secondary to retinal vein occlusion. We excluded patients with macular edema due to other ocular diseases. OCTA was performed in every patient to measure the size of foveal avascular zone. FAZ area of 0.6mm2 or less was taken as normal and any value above that was considered to be larger FAZ. IBM SPSS version 25 was used to analyze the data. Frequencies with percentages were used to present qualitative variables and mean ± SD were calculated for the quantitative variables. P-value ≤ 0.005 was taken as significant. \nResults:\xa0\xa0Mean age was 58.38 ± 7.51 years. There were 28 males and 22 females. Mean best-corrected visual acuity was 0.62 ± 0.26 logMar. The patients with normal FAZ area in DCP showed a mean BCVA of 0.51 ± 0.265 logMAR in comparison to those who had larger FAZ in DCP, where the mean BCVA was 0.75 ± 0.204 logMAR. DCP was larger in patients with CRVO than BRVO. \nConclusion:\xa0\xa0OCTA is a good diagnostic tool for qualitative and quantitative evaluation of the deep capillary plexus. Improvement in visual acuity is related with the size of the DCP in FAZ. \nKey Words:\xa0\xa0Retinal vein occlusion, Foveal avascular zone, Optical Coherence Tomograghy Angiography.