Assessment of Intravitreous Injections of Vitrase for Inducing Posterior Vitreous Detachment

Inclusion Criteria: * Moderately severe to severe non-proliferative diabetic retinopathy * Best Corrected Visual Acuity (BCVA) in Early Treatment Diabetic Retinopathy Study (ETDRS) with pinhole of 20/320 or better in study eye \& 20/50 or better in non-study eye. Exclusion Criteria: * Contraindications or hypersensitivities to Vitrase or anesthesia * Any significant illness that could be expected to interfere with trial * Prior Vitrase therapy * Either a past diagnosis of clinically significant macular edema (CME) in study eye that required treatment or current CME that may require focal laser treatment within the next 30 days * For either eye: ongoing ocular infection, inflammation or history of herpetic corneal lesion; an intravitreous injection within 30 days; glaucoma; intraocular pressure (IOP) of less than 5mmHg; retinal detachment or ocular tumors * For study eye: vascular occlusive disease of fundus; corneal, lenticular or ocular media abnormalities; a significant ocular trauma within 6 months; previous vitrectomy; any prior laser treatment, cryo-retinopexy or any intraocular surgery; either a partial or complete posterior vitreous detachment (PVD); myopia of 6 or more spherical diopters and/or axial length exceeding 26mm; significant retinal pathology