Intravenous Hyaluronidase with Urokinase as Treatment for Rabbit Retinal Artery Hyaluronic Acid Embolism

Although various salvage methods have been proposed to treat intraretinal artery hyaluronic acid embolism, their applications are still limited by various factors. The authors investigated the effectiveness of intravenous hyaluronidase with urokinase for resolving retinal artery hyaluronic acid embolism.

The anatomy of rabbit ophthalmic and fundus arteries (retinal and choroid artery) was studied. Approximately 0.35 ml of hyaluronic acid was injected into the ophthalmic artery to create a retinal artery embolism model. The rabbits were grouped randomly (groups A, B, C, D, E, and F) and given hyaluronidase with urokinase intravenously at different postobstruction time points (10, 20, 30, 40, 50, and 60 minutes). Saline was given to the control group. Fundus vascular (retinal and choroid artery) reperfusion status and the effectiveness of the solution on the obstruction of each group were observed for 5 days.

The animal model closely imitated actual hyaluronic acid ophthalmic/retinal artery obstructions. Three vascular conditions were observed after hyaluronidase with urokinase injection: total, partial, and no reperfusion. Groups A, B, and C showed a significantly higher overall solution effectiveness rate (total/partial reperfusion) compared with the control group (p = 0.001, p = 0.001, and p = 0.005, respectively). Solution effectiveness in groups D, E, and F showed no difference compared with the control group (p = 0.628, p = 1.000, and p = 1.000, respectively). The effectiveness of the solution drops dramatically if given after 30 minutes of obstruction.

The authors' method can indeed help resolve retinal artery hyaluronic acid obstruction. Intravenous hyaluronidase with urokinase technique shows possible potential to become a standardized treatment protocol for intraretinal artery hyaluronic acid embolism with further clinical tests.