Same-Site Revision of Failed Filtering Blebs:

Twenty-one procedures were performed at the same site as previous filtration operation to revise underfiltering or nonfiltering blebs. Fourteen of 21 (67%) revision procedures reduced the intraocular pressures to <19 mm Hg without hypotensive medications. Three additional same-site revisions (14%) were qualified successes requiring further medical treatment to maintain intraocular pressure at <22 mm Hg, for a total of 81% with a successful or qualified successful result. Four revisions (19%) failed to control intraocular pressure even with additional medications two required additional operative procedures. Subconjunctival episcleral membranes accounted for most of the bleb failures and responded favorably to same-site operative revision.