Changes in Retinal Vessel and Retinal Layer Thickness After Vitrectomy in Retinal Detachment via Swept-Source OCT Angiography

To compare postvitrectomy retinal and choroidal vessel density (VD) and retinal layer thickness between eyes with macula-off and macula-on rhegmatogenous retinal detachment (RRD) using swept-source optical coherence tomography (SS-OCT) and optical coherence tomography angiography (OCTA) and to identify OCTA factors associated with visual outcomes. We retrospectively reviewed 31 eyes that underwent pars plana vitrectomy for primary RRD. Eyes with macula-off and macula-on RRD were compared with healthy fellow eyes. Both OCT and OCTA were performed 6 months after surgery, and the macula-off RRD group was divided into two subgroups according to the presence of an outer retinal defect. The correlations between postoperative best-corrected visual acuity (BCVA) at 6 months and SS-OCT and OCTA measurements were analyzed. Twenty eyes with macula-off RRD and 11 eyes with macula-on RRD were included. In the macula-off RRD group, the central retinal thickness was significantly decreased 6 months postoperatively compared with the fellow eyes (228.9 ± 29.7 µm and 253.6 ± 27.7 µm, P = 0.009). In the outer retinal defect group, the choriocapillaris plexus (CCP) VD was significantly decreased compared with the fellow eyes (56.4% ± 4.8% and 60.2% ± 4.0%, P = 0.026). In the macula-off RRD group, the postoperative BCVA at 6 months correlated significantly with the ratio of the center CCP VD of the detached eyes to that of the fellow eyes (R2 = 0.207, P = 0.025). The CCP VD could be related to the anatomical restoration of the outer retinal layer in macula-off RRD. The CCP VD as determined by OCTA could be an indicator of the visual outcome after surgery in macula-off RRD.