Ophthalmic uses of tissue plasminogen activator

Tissue plasminogen activator [tPA] is a protease enzyme which catalyzes the conversion of plasminogen to plasmin. It is synthesized in vivo by human vascular endothelial cells and has also been manufactured in vitro, using recombinant DNA technology. Experimental and clinical investigations have been performed evaluating the efficacy of tPA in the treatment of different ophthalmologic disorders. Use of tPA has proven beneficial in the treatment of selected cases of hyphema, postoperative fibrin formation, and subretinal hemorrhage. Toxicity studies have demonstrated that 25 micro g of intraocular tPA is safe in nonvitrectomized eyes. We present a review of the literature with regard to the use of tPA