Intraocular cysticercosis.

Two intravitreal Taenia cysts were removed intact by pars plana vitrectomy from a 59-year-old woman who had never left the continental United States. The intraocular course of the cysts progressed from an initial chorioretinal location, accompanied by an intense focal inflammatory reaction, to free floating in the vitreous cavity within two months; thereafter, there was only a low-grade vitritis for an additional five months until removal. Light and electron microscopic studies suggested Cysticercus cellulosae as the infecting agent, although mature hooklets were absent. Local pork products were considered to be the source of the infection. Preretinal fibrosis and posterior subcapsular vacuoles were the final residua and did not progress after removal of the cysts. Although uncommon in the United States, cysticercosis should be considered in cases of focal necrotizing chorioretinitis.