Abstract
Abstract: :
Purpose: To assess the feasibility of making a localized retinal detachment for insertion of a retinal prosthesis by injection of distilled water into a vortex vein. Methods: Injection of distilled water was performed in 4 eyes of 4 Dutch–Belted rabbits. In each eye, 2 vortex veins (the infero–nasal and supero–temporal) were closed with sutures. A curved Lambert cannula was used to inject 6 ml, 3 ml, 2 ml, and 1 ml of distilled water in each eye, respectively, through one of the sutured veins. Injection rate was 1–2 ml/min. Intra–ocular pressure (IOP) was lowered 5 minutes after injection by anterior chamber paracentesis or core vitrectomy. After retinal detachment was created, a polyimide strip was inserted into the sub–retinal space in the area of detachment using an ab–externo surgical technique. Eyes were enucleated for histological study. Results: Retinal detachment occurred immediately after lowering of intra–ocular pressure. The detachment began in the area of the injected vortex vein and spread throughout the temporal half of the retina. In 2 eyes, we observed moderate exudation in the anterior chamber after paracentesis. Histology showed both choroidal and retinal detachment in the 1 eye studied. Conclusions: Injection of distilled water into a vortex vein may be a viable method of making a retinal detachment in animals for insertion of a sub–retinal prosthesis. The advantage of this procedure is that there is no need for a retinotomy to inject fluid into the sub–retinal space, making it less invasive. Possible complications of this procedure are prolonged detachment of the retina, choroidal detachment, hemorrhage and systemic effects of injecting distilled water. Chronic experiments are needed to see whether there are any significant long term complications.
Keywords: retina • retinal detachment