Abstract
Purpose: :
To study the feasibility of implantation of multiple retinal electrode arrays, in order to increase the field of vision in patients implanted with a retinal prosthesis.
Methods: :
Pigmented and albino rabbits were included in the study. Inactive electrode arrays of 2 mm width and 8 mm length, made of parylene or polyimide, were used for implantation. In each animal, multiple electrode arrays were implanted in the suprachoroidal space of the right eye. Each electrode array was implanted through a separate scleral incision. For implantation of 4 or more electrode arrays, scleral incisions were made at all quadrants of the eye. The animals were followed for 2 to 4 months. Follow up evaluations included color fundus photography, fundus fluorescein angiography (FA), optical coherence tomography (OCT), and electroretinography (ERG). Histological studies were performed using H&E staining.
Results: :
It was possible to implant multiple electrode arrays in the suprachoroidal space of a single eye in a single operation. In albino rabbits, the electrode arrays were easily visible in the suprachoroidal space, whereas in pigmented rabbits they were only detectable with OCT. Over time, there was no displacement of the electrode arrays, and the distance between the electrode arrays and the retina remained stable. There was no significant tilt or lift, and in each array, the distance between the neighboring electrodes and the retina was almost identical.
Conclusions: :
It was possible to safely implant multiple electrode arrays in the suprachoroidal space of the rabbit eye. The position of the electrode arrays remained stable over time.
Keywords: retina • retinal degenerations: hereditary • choroid