Treatment of Postvitrectomy Fibrin Using Intravitreal Tissue Plasminogen Activator
A 55-year-old African-American woman underwent 25G PPV, posterior capsulotomy, endolaser pan retinal photocoagulation, and intravitreal Ozurdex (Allergan, Irvine, CA) injection for nonclearing diabetic vitreous hemorrhage and coexisting macular edema. She had a history of Type 2 diabetes and chronic anterior uveitis after cataract surgery 1 year previously, which was controlled on topical prednisolone. She had recently undergone laser treatment of proliferative diabetic retinopathy 1 month ago. At the first postoperative review, 2 hours after surgery, hypotony was present and managed conservatively. The next day, her examination revealed an intraocular pressure of 12 mmHg and minimal anterior chamber inflammation, but intravitreal fibrin bands were observed in the vitreous cavity and on the retinal surface (Figure 1A). We injected 50 μg/0.05 mL of tissue plasminogen activator intravitreally. The fibrin bands resolved completely after 30 minutes with no complications (Figure 1B).
Post-PPV fibrin formation is caused by increased inflammatory mediators in the vitreous in diabetic patients after PPV surgery.1 Hypotony and laser photocoagulation are known risk factors for this condition.2 Tissue plasminogen activator is a thrombolytic agent that activates plasminogen into plasmin in the presence of fibrin.3 Jaffe et al4 have previously assessed the use of tissue plasminogen activator for post-PPV fibrin formation and it was found to be efficacious in lysing the fibrin reaction. Though cases of nonsevere fibrin reaction may be managed conservatively with topical steroids,2 we chose to use tissue plasminogen activator early in our patient's postoperative course because of her coexisting history of chronic uveitis that might have further exacerbated the fibrin reaction as a result of increased inflammatory reactivity.