To evaluate the interval between removal of intraocular silicone oil tamponade and retinal redetachment after pars plana vitrectomy, and to investigate factors influencing the length of the interval. The retrospective study included 42 eyes of 42 consecutive patients who experienced a retinal redetachment after silicone oil had been removed 8.0+/-6.2 months after an initial pars plana vitrectomy including intraocular silicone oil (5,000 centistokes) tamponade. Pars plana vitrectomy had been performed for proliferative vitreoretinopathy caused by complicated rhegmatogenous retinal detachment. The retina redetached 2 days to 5.5 months after silicone oil removal (mean +/- SD, 1.3+/-1.4 months; median, 18 days). Thirteen (30%) of all 42 redetachments occurred in the first 9 days, 21 (50%) of all 42 retinal redetachments occurred in the first 18 days, and 32 (75%) of all 42 retinal redetachments occurred in the first 50 days. The interval between silicone oil removal and retinal redetachment was statistically (by analysis of variance) independent of the method of silicone removal (transpupillary drainage vs via pars plana sclerotomies), refractive error of the eye (P = .62), time between initial pars plana vitrectomy and silicone oil removal (P = .99), visual acuity before silicone oil removal (P = .26), type of anesthesia (P = .69), gender (P = .80), and age (P = .48) of the patients. The risk of retinal redetachment decreases steeply with increasing time after silicone oil removal. Three to 5 months after oil removal, retinal redetachment becomes unlikely. The time of retinal redetachment is statistically independent of the method of silicone oil removal, refractive error, time between the preceding pars plana vitrectomy and silicone oil removal, visual acuity before silicone oil removal, type of anesthesia, and gender and age of the patents. These data may be important for scheduling reexaminations and for counseling patients in their planned activities after removal of intraocular silicone oil tamponade.