Heavy Versus Standard Silicone Oil Tamponade in Primary Retinal Detachment Surgery: a Systematic Review and Meta-Analysis.

Purpose: To compare the anatomical and functional outcomes of heavy and standard silicone oil (HSO and SSO) in primary rhegmatogenous retinal detachment (RRD), along with post-operative complications.

Methods: Meta-analysis conducted in accordance with PRISMA guidelines and registered on PROSPERO (CRD42024507061). We retrieved randomized trials, prospective and retrospective studies comparing HSO and SSO to manage primary inferior/posterior or complex RRDs published from 2000 to nowadays in PubMed/Medline-Embase-Cochrane-Scholar-Web of Science. This meta-analysis focused on primary success rates, best-corrected visual acuity (BCVA) improvement and postoperative complications.

Results: A total of 6 studies on 984 eyes (615 in SSO and 369 in HSO group) were included. In a fixed-effect model (p=0.112, I2 = 43.99%), HSO and SSO tamponades showed comparable primary anatomic success rates (OR 1.461, 95% CI: 0.890 to 2.399, p=0.134). Average BCVA improvement was similar between the 2 groups (I2 = 79.21%, WMD -0.071 LogMAR; 95% CI:-0.524 to 0.382, p=0.61). Conversely, HSO tamponade was associated with higher rates of IOP elevation (I2 = 37.42%, OR 2.073, 95% CI: 1.182 to 3.634, p=0.011) and emulsification (I2 = 16.43%, OR 2.953, 95% CI: 1.109 to 7.862, p=0.030). Finally, inflammation rates did not differ between HSO and SSO (I2 = 66.46%, OR 2.015, 95% CI: 0.234 to 17.323, p=0.523).

Conclusion: HSOs showed similar rates of primary anatomic success when compared to SSOs in complex primary RRDs. Although hindered by poor baseline values, visual outcomes were generally comparable among the two groups. In contrast, HSO group showed higher rates of post-operative IOP elevation and emulsification.