Postoperative hypotony after retinectomy in rhegmatogenous retinal detachment surgery: A systematic review and meta-analysis.
We estimate the incidence of postoperative hypotony after retinectomy performed during rhegmatogenous retinal detachment surgery and explore clinical, surgical, and methodological factors associated with hypotony risk. We include human clinical studies reporting postoperative intraocular pressure (IOP) outcomes after retinectomy or retinotomy for retinal detachment. Postoperative hypotony was defined as IOP ≤ 6 mmHg, with alternative thresholds (≤5 or ≤3 mmHg) retained for sensitivity analyses. A random-effects meta-analysis was used to pool hypotony incidence, with prespecified subgroup and sensitivity analyses according to retinectomy extent, tamponade strategy, hypotony definition, assessment timepoint, and vitrectomy gauge size. Study-level associations with visual outcomes and proliferative vitreoretinopathy (PVR) severity were also explored. Thirty-three studies comprising 2673 eyes were included. The pooled incidence of postoperative hypotony was 13.71% (95% CI, 10.40-17.40), with substantial heterogeneity (I² = 83.2%). Hypotony incidence did not increase linearly with retinectomy extent, and similar rates were observed for extents of 180°-269° and ≥ 270°. Stricter hypotony definitions and later postoperative assessment timepoints were associated with a higher reported incidence. A significant negative association was observed between hypotony incidence and visual improvement rates (Spearman ρ = -0.47, p = 0.03). In contrast, no significant study-level difference in hypotony incidence was observed according to PVR severity grouping or vitrectomy gauge size. Postoperative hypotony after retinectomy is a frequent and clinically relevant complication, moderately associated with poorer visual outcomes and influenced by methodological factors rather than retinectomy extent alone.