Prospective study initiated in September of 1994 in patients with complicated glaucoma who had had the Ahmed valve implanted.12 eyes from 12 patients were studied until February of 1996, with a median follow-up of 9.3+/-5.1 months (range 3-18 months). The most common diagnostic was pseudophakic glaucoma (8 ojos). 3 eyes had aphakic glaucoma and 1 eye had traumatic glaucoma. The success is defined as intraocular pressure (IOP)