Toxic anterior segment syndrome outbreak after vitrectomy and silicone oil injection

Purpose. To report a rare outbreak of toxic anterior segment syndrome (TASS) in 4 patients who underwent vitrectomy with silicone oil injection. Methods. Review of the medical charts of all patients who underwent surgery in the operating theater of our department during a 10-day period in May 2011. Results. We report on 4 patients who developed TASS after vitrectomy with silicone oil injection. The clinical presentation was typical of TASS, and different from the anterior chamber reaction that may occur after silicone oil injection. All cases were treated effectively with topical steroids, and the outbreak stopped after the silicone oil batch was exchanged. Conclusions. We discuss the possible mechanisms for this unusual TASS outbreak, and suggest the silicone oil as its cause.