A Retrospective Review of Patients With Proliferative Diabetic Retinopathy and Regression of PDR After Treatment With Ranibizumab

Current standard treatment for Proliferative Diabetic Retinopathy (PDR) is panretinal photocoagulation (PRP), but this treatment is inherently destructive and has several potential adverse effects on aspects of visual function, including constriction of peripheral visual fields and decreases in night vision, contrast sensitivity and color perception. Thus, therapeutic alternatives that might delay or obviate the need for PRP are desirable. It has been demonstrated that retinal neovascularization from PDR is highly responsive to anti-VEGF therapy, but it is unclear how long regression of retinal neovascularization is sustained after anti- VEGF therapy is halted in clinical practice.

It is possible that intravitreal ranibizumab treatment could prevent laser-associated vision loss by precluding the need for PRP as long as the eye continued to receive ranibizumab. Even if ranibizumab treatment was discontinued, it is possible that initial treatment with anti-VEGF therapy might improve visual outcomes substantially by delaying or preventing the need for PRP, and the infrequent frequency of administration of ranibizumab for DME (median 2 to 3 times in the second year of treatment) after the DME initially has resolved on anti-VEGF therapy suggests that monthly ranibizumab might not be needed to achieve control of PDR.

The Diabetic Retinopathy Clinical Research Network (DRCR network) is currently evaluating intravitreal ranibizumab treatment to see if can prevent laser-associated vision loss by precluding the need for PRP as long as the eye continued to receive ranibizumab. However, intravitreal injections carry the risk of serious complications. Ophthalmic complications include endophthalmitis in 2% of all injected patients cumulatively. Endophthalmitis is a vision threatening and can cause severe and permanent vision loss and even loss of the eye. Other complications include vitreous hemorrhage, retinal detachment, uveitis and glaucoma. This study will evaluate ranibizumab usage as the primary treatment for PDR in a busy private clinical practice.