Intracameral tissue plasminogen activator use in a large series of eyes with valved glaucoma drainage implants.

OBJECTIVE: To describe the efficacy and complications of intracameral tissue plasminogen activator (tPA) in a large series of glaucomatous eyes with valved glaucoma drainage implants (GDIs).
METHODS: A retrospective analysis of 620 Ahmed and Krupin aqueous shunts implanted between December 1992 and May 2001 identified 36 eyes treated with intracameral tPA for total or imminent tube obstruction by fibrin and/or blood. For a successful ocular outcome, tPA use must prevent the need for additional glaucoma surgery to replace or revise an occluded drainage implant.
RESULTS: Intracameral tPA successfully cleared or prevented tube occlusion by fibrin/blood clots in 32 (88.9%) of 36 eyes. Multiple tPA injections were administered in 38.9% of eyes, and the mean number of injections required to achieve successful outcomes was 1.6. The mean +/- SD tPA dose per injection was 9.8 +/- 3.1 micro g, and the mean +/- SD total tPA dose required to achieve successful outcomes was 15.5 +/- 9.9 micro g. For injections to be successful in totally occluded tubes (n = 31), the mean +/- SD intraocular pressure change 24 hours after tPA administration was -21.2 +/- 15.6 mm Hg. Significant complications, including severe hyphema, profound hypotony, and anterior chamber flattening, occurred after 10.9% of tPA administrations.
CONCLUSION: Intracameral tPA clears and prevents obstruction of valved GDIs by fibrin and/or blood clots.