Abstract
Purpose :
Retinal prosthesis is an engineered light sensor which is designed to receive the light evoked electrophysiology signals to adjacent remaining retinal cells which relay the signals to the brain visual cortex. Good ocular safety and biocompatibility of such a device is the first must-met criteria for further development. Rabbit eye size is closer to human eye than rodent while cheaper and easier handling than pig; however, many studies were performed in rodent eyes or pig eyes due to the thin and avascular retina of rabbit leading to low successful rate of subretinal implantation and lateral complication from surgical manuver. We developed a simple transcleral method to implant subretinal prosthesis using rabbit eye.
Methods :
Retinal prosthesis of 3mm x 4 mm x 300 µm with a power supplying tail design was implanted subretinally via a two-step surgical technique. The technique consists of external trans sclera/choroid implanting and internal vitrectomy and oil tamponading, using 25 G vitrectomy system. Ophthalmoscopic imaging and optical coherence tomography (OCT) analysis were performed to evaluate the anatomical relationship between the implant and the surrounding eye tissues.
Results :
Implant was successfully implanted in 19 rabbits out of 10 rabbits, with a 90% successful rate. The fundus image on the next day clearly demonstrated implant below optic nerve head where the rabbit visual streak is. OCT revealed overlying retina apposed to the electrode without retinal detachment (Fig1).
Conclusions :
This two-step surgical technique using 25 G vitrectomy system seems minimally invasive with little complication while with a consistent surgical successful rate.
This is an abstract that was submitted for the 2017 ARVO Annual Meeting, held in Baltimore, MD, May 7-11, 2017.