Beyond the Surface: Investigating Silicone Oil's Impact on Macular Perfusion in Macula-off Rhegmatogenous Retinal Detachment via OCTA

Purpose: This study aims to compare macular vessel density (VD) in eyes with macula-off rhegmatogenous retinal detachment (RRD) after vitrectomy with gas or silicone oil (SO) tamponade. Methods: Patients with macula-off RRD who underwent vitrectomy with either gas or SO tamponade were included. Best-corrected visual acuity (BCVA) and VD in superficial and deep retinal capillary plexuses (SCP and DCP), choriocapillaris (CCP), and foveal avascular zone (FAZ) were assessed using optical coherence tomography angiography (OCTA). Comparisons were made with the unaffected fellow eye. Results: Fifty patients (average age: 57.9±9.1 years) participated, with 26 eyes undergoing SO tamponade and 24 gas tamponade. No significant differences were found in baseline characteristics. Postoperative BCVA significantly improved in both groups. In the SO group, BCVA improved from 2.00±0.77 logMAR (20/2000 Snellen) to 0.95±0.52 logMAR (20/178 Snellen). In the gas tamponade group, BCVA improved from 2.12±0.70 logMAR (20/2636 Snellen) to 0.70±0.55 logMAR (20/100 Snellen) (p<0.001 for both groups). Moreover, the gas tamponade group achieved significantly better postoperative BCVA compared to the silicone oil group (p<0.05). SO tamponade group exhibited significantly lower VD in SCP, DCP, and CCP quadrants (p<0.05), while gas tamponade showed no significant differences. Conclusion: This study reveals a decrease in VD in SCP, DCP, and CCP induced by SO tamponade, suggesting potential toxic effects on macular perfusion. Gas tamponade resulted in superior BCVA outcomes and preserved VD. Further investigation into SO's underlying mechanisms and careful patient selection is warranted. Gas tamponade may offer better outcomes for macula-off RRD.