ObjectiveTo evaluate the changes in foveal avascular zone (FAZ) size and foveal microstructures in patients with rhegmatogenous retinal detachment (RRD) and to analyze the correlation between FAZ size, foveal microstructure changes and visual outcomes.MethodsA retrospective study. From January 2017 to January 2019, 79 RRD patients (79 eyes) diagnosed in Department of Ophthalmology in Baoding First Central Hospital were included in the study. The patients were divided into macula-off group (51 eyes), macula-on group (28 eyes). The unaffected fellow eyes were used as a control group. The retinas were reattachment in all eyes after first standard 23G PPV combined with silicone oil filling. Before and 3 months after surgery, all patients underwent a comprehensive ophthalmologic examination, including the measurement of BCVA and OCT angiography (OCTA) examination. The BCVA examination was performed using the international standard visual acuity chart, which was converted into logMAR visual acuity. The FAZ areas were evaluated with OCTA in the superficial capillary plexus layers by using 3 mm×3 mm images of the macular. The following postoperative foveal microstructures were evaluated:epiretinal membranes, macular edema, subretinal fluids, integrity of ellipsoidal zone and external limiting membrane. Pearson correlation analysis was used to analyze the correlation between FAZ area and BCVA. The correlation between macular microstructures and BCVA was analyzed by Spearman correlation analysis.ResultsAt 3 months after the removal of silicone oil, the FAZ area in the macula-off group, macula-on group and the control group were 0.447±0.041, 0.409±0.034, 0.335±0.027 mm2, respectively. Compared with the control group, the FAZ area in the macula-off group and macula-on group were enlarged, the difference was statistically significant (F=184.148, P＜0.05). The logMAR BCVA in the macula-off group and macula-on group were 0.800±0.180 and 0.386±0.160, respectively. There was significant difference in ellipsoidal zone rupture between the two groups (χ2=7.577, P=0.006). The results of correlation analysis showed that the area of FAZ and the incidence of ellipsoidal zone fracture after surgery were positively correlated with BCVA after surgery (r=0.329, 0.290; P=0.003, 0.010).ConclusionsThe FAZ area of RRD is enlarged after surgery. FAZ area and ellipsoid zone fracture are positively correlated with BCVA after surgery.