Nine patients (nine eyes) with iridocorneal endothelial (ICE) syndrome underwent trabeculectomy and received postoperative subconjunctival injections of 5-fluorouracil (5-FU) to enhance bleb formation (total 5-FU dose, 30-105 mg; mean, 53.8 mg). Eight eyes had undergone prior unsuccessful trabeculectomy. Four eyes had intraocular pressure (IOP) less than or equal to 21 mmHg on zero to two glaucoma medications after 6 to 54 months of follow-up (mean, 25.3 months). Five eyes required repeat surgery within 2 to 13 months and were considered failures. All five eyes that failed received a Molteno drainage implant. Progressive endothelial proliferation may explain late onset bleb failure and the relative ineffectiveness of 5-FU in this condition.