[Visual outcome after silicon oil surgery].

The question as to whether silicone oil is toxic to the retina has not been resolved to this day. We have attempted to find evidence of retinal toxicity by studying the development of visual acuity in eyes operated on with silicone oil. We selected these eyes from a cohort of about 500 that had attached retina, no glaucoma and no keratopathy. The average visual acuity increased continuously over 2 years if all extraretinal factors influencing visual acuity are excluded. Although in eyes from which silicone oil had been removed visual function developed better than in those in which it remained indefinitely, this could not be attributed to a toxic effect of silicone oil, since the difference was apparent even while eyes in both cohorts where still filled with oil. The difference is more probably a result of patient selection. In individual cases in which silicone oil was not removed for up to 8 years the visual acuity remained stable. An analysis of the patients with loss of vision despite attached retinas yielded causes that were essentially specific to the underlying disease. We found no clinical evidence suggestive of a toxic effect of silicone oil.