RESUMO
PURPOSE: To evaluate the possibility of inducing a posterior vitreous detachment (PVD) by intravitreal injection of streptokinase using electron microscopy and electrophysiological study. METHODS: The current study was performed on 30 eyes of 15 male white rabbits. The rabbits were divided into three equal groups. The right eye of the three groups received an intravitreal injection of streptokinase at three different concentrations (150, 1,500 and 15,000 IU in 0.1 mL balanced salt solution) in the mid vitreous cavity. The left eye in all animals received an intravitreal injection of balanced salt solution and was considered the control group. Electroretinography was performed 1 day and 1 week after injection. The rabbits were killed after 10 days, and the enucleated eyes were processed for transmission and scanning electron microscopic examination. RESULTS: In Group 1, scanning electron microscopy showed the retinal surface covered with thin collagen fibers, whereas in Group 2, a complete PVD with bare retinal surface was seen. Group 3 showed a bare retinal surface with hemorrhagic reaction and toxic effects on the retina by transmission electron microscopy. CONCLUSION: An intravitreal injection of 1,500 IU of streptokinase can lead to a PVD without major toxic effects on the retina.
