Surgical Outcomes and Complications Following Silicone Oil Removal in Retinal Detachment Surgery at KCMC Eye Department, Northern Tanzania (2020-2023)

Abstract

Background and Aims: Retinal detachment (RD) is the separation of the neurosensory retina from the retinal pigment epithelium, causing subretinal fluid buildup. Pars plana vitrectomy (PPV) with silicone oil tamponade is commonly used to treat retinal detachment. The aim of the study was to evaluate the anatomical and functional outcomes and to identify the postoperative complications following silicone oil removal in retinal detachment surgery. Study Design: Retrospective cohort study. Place and Duration of Study: Eye department in KCMC hospital in Northern Tanzania, from January 2020 to December 2023. Methodology: A total of 231 eyes with a documented six-month follow-up after silicone oil removal were included. Data were collected using a structured data collection form. Good visual outcome was categorized as visual acuity ≤ 1 LogMAR, and anatomical success was defined as retinal reattachment after oil removal. Statistical analysis was performed using SPSS version 25. Associations between clinical variables and outcomes were assessed using the Chi-square test, univariate and multivariable analysis, with a p-value ≤0.05 considered statistically significant. Results: Anatomical success was achieved in 66.7% and functional success in 42% of eyes. Multivariable analysis showed that retinal re-detachment significantly reduced the likelihood of a good visual outcome (ARR: 0.33, 95% CI: 0.20- 0.54, p< 0.001), whereas good baseline visual acuity (≤1 LogMAR) increased the likelihood (ARR: 1.71, 95% CI: 1.31- 2.23, p<0.001). Preoperative proliferative vitreoretinopathy increased the risk of re-detachment (ARR: 1.57, 95% CI: 0.99- 2.46, p = 0.05), while myopia was associated with a 68% reduced risk (ARR: 0.32, 95% CI: 0.11- 0.94, p = 0.04). The most common postoperative complications comprised of retinal re- detachment (33.3%), cystoid macular edema (14.8%), epiretinal membrane formation (12.1%), ocular hypertension (10.4%), keratopathy (7.5%), and hypotony (7.5%). Conclusion: A good baseline visual acuity and retinal attachment after oil removal were strongly associated with a favorable visual outcome. Proliferative vitreoretinopathy was a major risk factor for postoperative retinal re-detachment, while myopia was linked to a lower risk. The apparent protective effect in myopic eyes may have been attributed to the use of prophylactic panretinal photocoagulation, which could have reduced the risk of retinal re-detachment.