Management of postvitrectomy diabetic vitreous hemorrhage with tissue plasminogen activator (t-PA) and volume homeostatic fluid-fluid exchanger

The incidence of recurrent vitreous hemorrhage of proliferative diabetic re tinopathy following posterior vitrectomy ranges from 29% to 75% in reported series. Fluid-gas exchange and vitreous cavity lavage are the popular meth ods of treating this kind of recurrent hemorrhage. The fluid-gas exchange c annot offer clear vision immediately after the procedure. To improve the fu nction of the classic vitreous cavity lavage, we designed a volume homeosta tic fluid-fluid exchanger - Chen's I/A device. Tissue plasminogen activator (t-PA) is a protease that preferentially converts fibrin-bound plasminogen to the active proteolytic enzyme, plasmin. It has been clinically and expe rimentally proven effective in lysis of postvitrectomy blood clot and fibri n formation. When the blood clot is formed in the vitreous cavity, intravit real injection of t-PA can convert plasminogen to plasmin and remove the cl ot. From July 1999 to January 2000, ten eyes of postvitrectomy diabetic vit reous hemorrhage (PDVH) were collected. In each case, 4 days after intravit real injection (IVI) of t-PA (30 mug), vitreous cavity lavage was performed with Chen's I/A device. Of these cases, 8 eyes (80%) experienced an immedi ate clearing of the vitreous cavity. Early complications included anterior hyaloid fibrovascular proliferation (2 eyes) and postoperative intraocular pressure elevation (3 eyes). On the basis of the results of this study, our conclusion is that volume homeostatic vitreous cavity lavage, combined wit h intravitreal injection of t-PA, is an excellent method for treatment of p ostvitrectomy diabetic vitreous hemorrhage but, in cases of PDVH with iris rubeosis, the advantage of this procedure is uncertain.