Reorganization of the perifoveal microvasculature after macular hole closure assessed via optical coherence tomography angiography

Purpose: To quantify short-term microvascular changes after pars plana vitrectomy (PPV) with internal limiting membrane (ILM) peeling in patients with idiopathic macular hole (IMH) using optical coherence tomography angiography (OCTA). Design: Cohort Study. Participants: This study included patients with IMH. Affected eyes were compared with fellow eyes. Methods: 6 x 6 mm OCTA (Zeiss Angioplex, Zeiss Meditec, Dublin, CA, USA) images of the study eye and fellow eye were acquired one day before surgery, 4 weeks and 12 weeks after surgery. Microvascular alterations in the superficial and deep capillary plexus were assessed by measuring vessel density and the shortest distance to the surrounding vessels of all intercapillary pixels. Only vessels enclosed by an ETDRS Grid centered on the fovea were analyzed. Main outcome measures: Change of vessel density and vessel distance to baseline. Results: OCTA images of the 15 study and 15 fellow eyes of 15 included patients (mean +/- SD of age: 67.89 +/- 5.2 years) were analyzed and revealed a significant increase in vessel density and decrease in vessel distance of the deep capillary plexus in study eyes 4 weeks after surgery compared to baseline. Our superficial capillary plexus findings were the inverse, namely a significant decrease in vessel density and increase in vessel distance. Post operative microvascular changes proved to be closely associated with the extent of retinal thickness reduction in the perifoveal deep capillary plexus. Conclusions: IMH closure after PPV and ILM peeling caused a significantly improved microvasculature in the deep capillary plexus, which may represent reorganized perifoveal microvasculature due to the regression of cystoid spaces.