Entwicklung eines minimal-invasiven Retinaimplantats

ZusammenfassungHintergrundZiel des Projekts ist es, ein minimal-invasives Retinaimplantat-System zu entwickeln, mit dessen Hilfe es erblindeten Patienten mit distalen Netzhautdegenerationen ermöglicht werden soll, Bildinformationen durch kodierte elektrische Stimulation verbliebener Netzhautneurone wahrzunehmen.MethodeDas technologische Konzept des minimal-invasiven Retinaimplantats wurde im Rahmen einer Machbarkeitsstudie entwickelt. Zwei unterschiedliche Serien von Testobjekten wurden entworfen, gefertigt und anschließend in vitro und in vivo erprobt.ErgebnisseAls Resultat des Entwicklungsprozesses wurde ein System konzipiert, bei dem stimulierende Mikroelektroden als einziger Implantatanteil ab externo via Sklera und Aderhaut in das Augeninnere eindringen, während alle weiteren Implantatkomponenten auf der äußeren Skleraoberfläche befestigt werden. Die Elektrodenpenetration sowie die chirurgische Implantationstechnik konnten in mehreren Versuchsserien erfolgreich erprobt werden. Eine langzeitige Bioverträglichkeitsuntersuchung an Primaten wurde mit ersten Testobjekten erfolgreich initiiert.SchlussfolgerungenDie bisher vorliegenden Ergebnisse sprechen für eine technologische Machbarkeit, eine leicht handhabbare chirurgische Anwendungsmöglichkeit und gute langzeitige Bioverträglichkeit des hier konzipierten minimal-invasiven Retinaimplantat-Systems.AbstractPurposeIt 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.MethodsThe 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.ResultsThe 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.ConclusionResults so far demonstrate the conceptual feasibility, easy-to-perform surgical application, and long-term biocompatibility of the newly designed minimally invasive retinal implant system.

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