Combined Light–Heavy Silicone Oil Endotamponade Compared with Heavy or Light Silicone Oil Endotamponade for Complex Rhegmatogenous Retinal Detachment: A Randomized Controlled Trial

INTRODUCTION: To compare the clinical outcomes and postoperative complications of combined light-heavy silicone oil (L-HSO), heavy silicone oil (HSO), and light silicone oil (LSO) endotamponade for complex rhegmatogenous retinal detachment (RRD) with superior and inferior retinal breaks. METHODS: In this prospective randomized controlled trial, 90 patients with primary complex RRD involving superior and inferior retinal breaks and proliferative vitreoretinopathy (PVR) grade C or higher were randomized to receive L-HSO, HSO, or LSO endotamponade after pars plana vitrectomy. Ultimately, 74 patients (74 eyes) completed the 12-month follow-up and were included in the final statistical analysis. The primary outcome was primary anatomical success rate. Secondary exploratory outcomes included best-corrected visual acuity (BCVA), intraocular pressure (IOP), and postoperative complications. RESULTS: During the follow-up period, no statistically significant differences in primary anatomical success rates were observed among the three groups, although the combined L-HSO group showed a numerically higher primary anatomical success rate (100.0%). In addition, exploratory analyses suggested better BCVA in the combined L-HSO group than in the HSO group before removal of silicone oil (ROSO) and at 6 months after ROSO than in the LSO group at 6 months after ROSO (P < 0.05); no significant differences were observed at 12 months after ROSO. Regarding postoperative complications, the combined L-HSO group showed lower incidences of cataract progression, emulsified silicone oil droplets adhering to the posterior capsule, silicone oil emulsification in the vitreous cavity, anterior PVR, and elevated IOP than the HSO group (all P < 0.05). CONCLUSIONS: Combined L-HSO endotamponade may represent a potential endotamponade strategy for complex RRD with superior and inferior retinal breaks. Although the combined L-HSO group showed a numerically higher primary anatomical success rate and potentially favorable functional and safety findings, these results should be interpreted as exploratory and require confirmation in adequately powered studies. CLINICAL TRIAL REGISTRATION: Chinese Clinical Trial Registry identifier: ChiCTR2600132242.