Clinical Outcome of Cystoid Macular Edema in Silicone Oil-Filled Eyes

Purpose: To investigate the clinical outcome of cystoid macular edema (CME) in eyes undergoing silicone oil (SO) tamponade with subsequent SO removal (SOR). Methods: A retrospective case series of adult patients with CME treated with SO tamponade and SOR was conducted between January 2015 and January 2021. Exclusion criteria included eyes with a prior SO tamponade, those that did not undergo SOR, or those with infectious/inflammatory diagnoses. The primary outcomes were the incidence and resolution rates of CME in eyes with SO tamponade that had undergone SOR. The secondary outcomes included changes in best-corrected visual acuity (BCVA) and central field thickness (CFT). Results: Nineteen eyes of 19 patients (58% men) aged 52 years (interquartile range [IQR], 45-66 years) met the study inclusion criteria. The median (IQR) follow-up duration post SOR was 22 (8-35) months. The mean CFT decline for the CME-resolved cases was 13.1 µm/mo (P = .257). CME resolved in only 10 eyes (53%), 7 (67%) of which occurred after SOR. The median (IQR) BCVA was 20/400 (20/200 to 20/1262) at CME diagnosis and 20/796 (20/252 to hand motions) after SOR, with 0.184 worsening in logMAR BCVA (P = .340). Medical treatment was not associated with CME resolution compared with observation (50% vs 89%, respectively; P = .069). Eyes with proliferative vitreoretinopathy (PVR) had a higher rate of persistent CME compared with eyes with other diagnoses (78% vs 10%, respectively; P = .005). Conclusions: Nearly half had nonresolution of CME after SO was removed. The VA at the last follow-up was unaffected by CME resolution. Preoperative PVR may be a risk factor for unresolved CME.