Medical Management of a High Bleb Phase after Trabeculectomies

In the first 2 months after trabeculectomy, elevated intraocular pressure (IOP) associated with a high bleb develops in some patients. This has been referred to as an encysted bleb, and some have recommended surgical techniques to repair it and to restore controlled IOP. This clinical picture occurred in 18 of 181 eyes (10%) undergoing simple trabeculectomy with a limbus-based conjunctival flap and tenonectomy. It did not occur among 69 eyes in which trabeculectomy with a fornix-based flap was combined with extracapsular cataract extraction (ECCE). Its occurrence may, therefore, be related to surgical technique. In eyes with this syndrome, the authors used IOP-lowering eyedrops and/or pills, along with continued corticosteroid eyedrops. None required surgical manipulation. All 18 eyes achieved long-term IOP control, and in 14 all medications were ultimately discontinued. An hypothesis is suggested to explain the occurrence of this event and the rationale for this therapy. A trial of IOP-lowering treatment is indicated in the management of a high bleb phase after filtering surgery.