Needling revision of trabeculectomies bleb morphology and long-term survival.

To assess the long-term success rate and to determine factors that predict survival after 5-fluorouracil-augmented needling revision of poorly functioning trabeculectomy blebs. Prospective observational cohort study. Eighty-one consecutive patients undergoing bleb needling. Survival analysis was performed after a minimum of 2 years' follow-up. Cox proportional hazards regression analysis was used to test the association between survival and study variables, including bleb morphology. Intraocular pressure (IOP) reduction by >20% and to 20% and to