The prevention and treatment of neovascular glaucoma in diabetic patients presents a difficult clinical challenge. This report presents the pathologic findings in a juvenile onset diabetic patient who underwent panretinal photocoagulation. She subsequently developed neovascular glaucoma, was treated with the the Krupin-Denver valve implant, and received cyclocryotherapy after the filtering surgery failed to maintain a normal intraocular pressure. The pathologic findings resulting from each treatment modality are presented with emphasis on the failed intraocular valve. A fibrous ingrowth surrounded the valve, and a foreign body granulomatous response was present.