♦ 연사: Joseph F. Rizzo III
♦ 일시: 2015년 11월 5일(목) 오후 5:00~6:00
♦ 장소: 서울대학교 제1공학관(301동) 118호

Abstract:
 The visual prosthesis system was designed for patients who are blind due to age-related macular degeneration or retinitis pigmentosa. The highdensity Boston device is packaged in a hermetically sealed titanium case, and supports 256+ channels. In vitro testing results will be presented; in addition, the 11 mm diameter x 2.5 mm thick assembly has been implanted into two mini-pigs, including a new, coiled-cable electrode array design that offers greater flexibility in its surgical placement compared to our former design. Custom surgical tools were also refined for the new implants. In separate animal studies, we have also implanted sub-retinal penetrating electrode arrays and compared OCT scans of such arrays to histological data obtained from the same mini-pigs. We have also wirelessly tested our stimulator chip. The ASIC provides programmable, bi-phasic current waveforms at the output electrodes, based on commands received via a 6.78 MHz data link. In between stimulation cycles, the electrodes are shorted to ground (i.e., the titanium case) for at least 200 μsec. The implant also sends data back to the control system through a lower-bandwidth channel using load-shift keying. The design’s safety is ensured by on-board electrode voltage monitoring, hardware and software stimulus charge limits, error checking of data, and a suite of self-test and performance monitoring features. We have tested our ASIC in both wired and wireless configurations. This >256 channel device is appropriate for chronic implantation with our team’s minimally-invasive subretinal surgical implantation techniques, and its sophisticated out-bound or ‘reverse’ telemetry features will facilitate optimization of stimuli for each patient and safe operation of our high-density retinal prosthesis system. Further in vivo pre-clinical trials are planned.

Biography:
♦ Joseph Rizzo is a native of New Orleans, Louisiana and a graduate of Louisiana State University and Louisiana State University Medical School in New Orleans, where he received the “Dean’s Award” in recognition of outstanding leadership and performance. He completed an internship in adult medicine at the University of California at Los Angeles Medical Center, followed by a neurology residency at Tufts University - New England Medical Center and then an ophthalmology residency at Boston University. He then performed a clinical fellowship in neuro-ophthalmology under Dr. Simmons Lessell in the Harvard Medical School Department of Ophthalmology at the Massachusetts Eye and Ear Infirmary. He is Board-Certified in both ophthalmology and neurology. Following completion of clinical training Dr. Rizzo joined the full-time academic faculty at the Massachusetts Eye and Ear Infirmary and received a five-year Physician Training Award from the National Institutes of Health. The laboratory training was under the supervision of Richard Masland, Ph.D.
♦ Dr. Rizzo initiated the Retinal Implant Project in 1988 and since then has divided his professional time equally between the evaluation of patients with neuro-ophthalmologic disease and serving as codirector of the Retinal Implant Project. Dr. Rizzo has served as Director of the Neuro-Ophthalmology service at Harvard Medical School since 2006.