title: Artificial vision by direct optic nerve electrode (AV-DONE) implantation in a blind patient with retinitis pigmentosa.
abstract: The purpose of this study was to evaluate the efficacy and safety of artificial vision by using a direct optic nerve electrode (AV-DONE) in a blind patient with retinitis pigmentosa (RP). This device, comprising three wire electrodes (0.05 mm in diameter), was implanted into the optic disc of a patient with RP with no light perception vision and the device was left implanted. Six months later, visual sensations were elicited by electrical stimulation through each electrode and the thresholds for the phosphene perception elicited by pulses of 0.25-ms duration/phase and a pulse frequency of 320 Hz were 30, 5, and 70 microA for each electrode. The phosphenes, which ranged in size from that of a match head to an apple, were round, oval, or linear, primarily yellow, and focally distributed. The area of the phosphenes changed when the electrical stimulation was supplied from different electrodes. No complications arose during the follow-up period. Localized visual sensations were produced in a blind patient with advanced RP, suggesting that our system could lead to the development of a useful visual prosthesis system.
authors.affiliation: Department of Ophthalmology, Osaka University Medical School, Suita, Osaka, Japan. sakaguh@ophthal.med.osaka-u.ac.jp
authors.forename: Hirokazu
authors.initials: H
authors.lastname: Sakaguchi
authors.forename: Motohiro
authors.initials: M
authors.lastname: Kamei
authors.forename: Takashi
authors.initials: T
authors.lastname: Fujikado
authors.forename: Eiji
authors.initials: E
authors.lastname: Yonezawa
authors.forename: Motoki
authors.initials: M
authors.lastname: Ozawa
authors.forename: Carmen
authors.initials: C
authors.lastname: Cecilia-Gonzalez
authors.forename: Orlando
authors.initials: O
authors.lastname: Ustariz-Gonzalez
authors.forename: Hugo
authors.initials: H
authors.lastname: Quiroz-Mercado
authors.forename: Yasuo
authors.initials: Y
authors.lastname: Tano
mesh_terms: D000328:Adult; D001766:Blindness / Q000209:etiology / Q000601:surgery*; D004558:Electric Stimulation / Q000295:instrumentation; D004567:Electrodes, Implanted; D005240:Feasibility Studies; D005260:Female; D006801:Humans; D009900:Optic Nerve; D019919:Prosthesis Implantation; D012174:Retinitis Pigmentosa / Q000150:complications*; D014796:Visual Perception