Optical coherence tomography angiography evaluation of retinal and choriocapillaris changes after pars plana vitrectomy for macula-off rhegmatogenous retinal detachment: perfluoropropane versus silicone oil tamponade

Rhegmatogenous retinal detachment (RRD) with macular involvement may lead to persistent visual impairment despite successful anatomical repair. Different intravitreal tamponade agents used during pars plana vitrectomy (PPV) may variably affect retinal and choroidal microcirculation. This study aimed to evaluate longitudinal changes in retinal vascular layers and choriocapillaris flow (CCF) using optical coherence tomography angiography (OCT-A) in macula-off RRD eyes treated with perfluoropropane (C3F8) gas or silicone oil (SO) tamponade. In this prospective cohort study, 30 eyes of 30 patients with macula-off RRD who underwent PPV using either C3F8 gas (n = 13) or 1000-cSt SO (n = 17) were included, along with 30 healthy fellow eyes as controls. OCT-A measurements were obtained at 2, 3, 5, and 6 months postoperatively. Foveal and parafoveal superficial capillary plexus (SCPVD), deep capillary plexus (DCPVD) vessel density, foveal avascular zone (FAZ), CCF, and macular thickness were analyzed and compared longitudinally and with healthy fellow eyes. Parafoveal SCPVD and macular thickness were significantly reduced in the SO group compared with controls at all time points (p < 0.05). CCF measurements in both 1-mm and 2-mm radius areas were significantly lower in the SO group at 5 and 6 months, even after SO removal (p < 0.05). In contrast, the C3F8 group showed transient reductions in DCPVD at 2 and 3 months, with subsequent recovery. FAZ area did not differ significantly between groups. Correlation analysis revealed a strong negative correlation between changes in SCPVD and changes in BCVA in the SO group. SO tamponade is associated with persistent impairment of macular microcirculation and CCF that does not fully recover after oil removal, whereas retinal vascular changes following C3F8 tamponade appear largely reversible. OCT-A may be a valuable noninvasive tool for guiding tamponade selection and determining optimal timing of SO removal in macula-off RRD surgery.