Anatomical and Functional Outcomes After Pars Plana Vitrectomy for Giant Retinal Tear-Related Detachment: The Manchester GRT Study.

PURPOSE: To evaluate anatomic and functional outcomes after primary pars plana vitrectomy (PPV) for giant retinal tear-related rhegmatogenous retinal detachment (GRT-RRD) and to compare outcomes between gas and silicone oil tamponade. DESIGN: Retrospective, single-centre cohort study. PARTICIPANTS: 110 consecutive eyes undergoing primary PPV for GRT-RRD at a tertiary vitreoretinal service (2012-2024). METHODS: Demographic, preoperative, and intraoperative variables were extracted from routinely collected clinical records. Baseline characteristics and outcomes were first compared between silicone oil and gas groups using univariable analyses. To address confounding by indication, full propensity score matching was then performed. Single surgery anatomical success (SSAS) was assessed with Firth logistic regression and final best-corrected visual acuity (BCVA) with weighted linear regression using G-computation. MAIN OUTCOME MEASURES: SSAS, final anatomic success (FAS), and final BCVA (logMAR). RESULTS: Mean age was 50.1 (16.0) years, and 83/110 (75.5%) patients were male. Macular detachment was present in 46/110 (41.8%) eyes. Gas tamponade was used in 76/110 (69.1%) eyes (SF6 5/110 [4.5%], C2F6 52/110 [47.3%], C3F8 18/110 [16.4%]) and silicone oil in 34/110 (30.9%). SSAS was achieved in 97/110 (88.2%) eyes and FAS in 103/110 (96.3%). After propensity score matching, male sex was associated with higher odds of SSAS (OR 4.54, 95% CI 1.75-11.75; p=0.002), whereas proliferative vitreoretinopathy (PVR) grade C was associated with lower odds of SSAS (OR 0.10, 95% CI 0.02-0.45; p=0.003). In the overall matched cohort, silicone oil trended toward worse final BCVA versus gas (MD +0.138 logMAR, 95% CI -0.015 to 0.291; p=0.077) with similar SSAS. In macula-on matched eyes, silicone oil was associated with worse final BCVA (MD +0.179 logMAR, 95% CI 0.018 to 0.341; p=0.030) with comparable SSAS (92.6% vs 90.0%; p=1.000). CONCLUSIONS: Primary PPV for GRT-RRD achieved high rates of SSAS and FAS, with C2F6 used as the most common tamponade. After adjustment for confounding, male sex was associated with higher SSAS and PVR grade C with lower SSAS. SSAS were comparable between groups, while visual outcomes showed a trend toward better outcomes with gas in the overall cohort; macula-on analysis should be interpreted cautiously due to small sample size.