Needle revision of filtering blebs.

The modern version of trabeculectomy is associated with a very high success rate. As time progresses after surgery, failure of filtration, however, is common, as are problems with filtering blebs such as leaks and dysesthesia. Needle revision of filtering blebs is a useful adjunct to failed, failing, leaking, or dysesthetic trabeculectomy filters and can be performed in a variety of settings and techniques with fairly good results. Although varied techniques have been reported, there is no definitive "best" surgical approach. Needle revision should be considered before more aggressive surgical intervention, and in some cases before additional medical therapy. Owing to the paucity of rigorously conducted clinical studies, this review focuses on clinical experience with bleb needle revision.