[Development of a minimally invasive retinal implant system].
OBJECTIVE
It was the aim of this project to develop a minimally invasive prosthetic retinal implant system for the rehabilitation of blind patients suffering from distal retinal degenerations. For this purpose, encoded image information will be transferred to surviving retinal neurons by electrical stimulation applied via intraretinal microelectrodes.


METHODS
The technological concept was generated in a feasibility study of alternative approaches to minimally invasive retinal prostheses. Then two series of test implants were fabricated and applied in different in vitro- and in vivo- studies before a long-term implantation trial was initiated.


RESULTS
The conceptual design process was resulting in a system with stimulating microelectrodes penetrating the sclera and choroid ab externo, and with all other implant components in episcleral position. Microelectrode penetration and surgical application techniques were successfully tested in several series of experiments. Finally, a long-term application of test devices was successfully initiated.


CONCLUSIONS
Results so far demonstrate the conceptual feasibility, easy-to-perform surgical application, and long-term biocompatibility of the newly designed minimally invasive retinal implant system.
Gerding
H
H
Abt. für Retinologie, Augenzentrum Klinik Pallas, Louis-Giroud-Strasse 20, CH-4600 Olten, Schweiz. hgerding@klinik-pallas.ch
D000818:Animals; D001766:Blindness / Q000503:physiopathology / Q000534:rehabilitation*; D004599:Electric Stimulation Therapy / Q000295:instrumentation*; D004567:Electrodes, Implanted; D006801:Humans; D008252:Macaca fascicularis; D008839:Microelectrodes; D019060:Minimally Invasive Surgical Procedures / Q000295:instrumentation; D019736:Prostheses and Implants; D011474:Prosthesis Design; D012160:Retina / Q000503:physiopathology; D012162:Retinal Degeneration / Q000503:physiopathology / Q000534:rehabilitation*; D014795:Visual Pathways / Q000503:physiopathology