Tissue plasminogen activator and glaucoma drainage implants.

PURPOSE: The tube lumen of a glaucoma drainage implant is prone to occlusion by a blood or fibrin clot due to its small caliber, relatively low flow rate, and the plasmoid nature of the aqueous humor passing through it in the early postoperative period. The use of tissue plasminogen activator in the management of drainage tube obstruction is described herein.
METHODS: Two cases of drainage tube obstruction in patients with neovascular glaucoma treated with an intracameral injection of tissue plasminogen activator are reported.
RESULTS: Resolution of tube obstruction following tissue plasminogen activator administration with spontaneous lowering of the intraocular pressure and bleb formation was achieved in both cases. Differentiation of tube obstruction from other causes of elevated intraocular pressure following installation of glaucoma drainage devices is discussed.
CONCLUSION: The intracameral injection of tissue plasminogen activator may relieve drainage tube obstruction secondary to a blood or fibrin clot, even in the absence of any visible clot covering the proximal tube ostium or within the anterior chamber portion of the tube. This approach should be considered, in selected cases, prior to more invasive surgical revision.