Comparison of gas alone versus intravitreal TPA and gas in treating large submacular hemorrhages

Abstract

Abstract: : Purpose: To compare the efficacy of using gas alone to using intravitreal tissue plasminogen activator (TPA) and gas in treating large submacular hemorrhages Methods:A retrospective review of 17 patients was performed who presented with large submacular hemorrhage secondary to age–related macular degeneration. Of these, 4 patients underwent an injection of 0.3 cc of 100% C₃F₈ gas alone. Ten patients underwent gas injection first followed by intravitreal TPA injection (100 µcg) 24 hours later if the subretinal blood was not significantly displaced from the macula with gas alone. Three patients were treated first with intravitreal TPA followed by gas injection 24 hours later. Patients with intraocular gas tamponade underwent prone positioning for 2 weeks. Fundus photography was performed pre–operatively and post–operatively. Fluorescein angiography was performed whenever there was adequate clearing of the hemorrhage. Results: In the patients with large submacular hemorrhage, C₃F₈ injection alone sufficiently cleared the blood for angiographic evaluation in only 2 of the 14 patients who had gas injection either alone or first. Gas injection showed equal displacement of the blood in all directions. Of those who subsequently underwent TPA injection, 8 out of 10 showed a further dramatic movement away from the macula within 24 hours, with significant inferior movement of the blood. All of the patients who were treated first with intravitreal TPA showed definite inferior collection and sagging of the blood within 24 hours. All three patients who were given gas injection following TPA showed significant further displacement of the blood away from the macula after the gas injection. Underlying choroidal neovascular membranes were identified in eight patients who had adequate clearing to undergo fluorescein angiography. No significant complications were noted. Conclusions: Gas injection alone with prone positioning can sometimes mechanically displace subretinal blood in AMD which has undergone partial fibrinolysis. Photographic evidence shows that TPA can rapidly induce enzymatic liquefaction of subretinal blood following intravitreal injection. This offers clinical evidence that TPA is able to cross the human retina. TPA after gas injection or vice versa often leads to more effective blood liquefaction plus a definite increase in displacement of the blood. Pneumatic displacement of submacular hemorrhage can be enhanced with intravitreal TPA in cases where gas alone does not offer sufficient displacement for angiographic evaluation and treatment.

Keywords: age–related macular degeneration • enzymes/enzyme inhibitors • retina