Retinitis pigmentosa (RP) and age-related macula degeneration (AMD) lead to the degeneration of the light sensitive cells of the retina (photoreceptors), leading to blindness. Clinical trials are investigating the feasibility of replacing the function of the photoreceptors with an electronic device that will electrically stimulate the remaining cells of the retina to generate visual perceptions. Blind humans have used prototype retinal prostheses with a limited number of stimulating electrodes to distinguish basic shapes and to detect motion. Based on these encouraging results, the current focus is being shifted from feasibility studies to the development of a high-resolution retinal prosthesis which will be capable of stimulating the retina at thousands of individual points. Simulations of prosthetic vision predict that 1000 electrodes will be needed to restore visual function such as face recognition, reading, and mobility. Advances in microelectronics and packaging are required to enable such a device.
James Weiland received his B.S. from the University of Michigan in 1988. After 4 years in industry with Pratt & Whitney Aircraft Engines, he returned to Michigan for graduate school, earning degrees in Biomedical Engineering (M.S. 1993, Ph.D. 1997) and Electrical Engineering (M.S. 1995). He joined the Wilmer Ophthalmological Institute at Johns Hopkins University in 1997 as a postdoctoral fellow and, in 1999, was appointed an assistant professor of ophthalmology at Johns Hopkins. Dr. Weiland was appointed assistant professor at the Doheny Eye Institute-University of Southern California in 2001. Currently, Dr. Weiland is an Associate Professor of Ophthalmology and Biomedical Engineering, University of Southern California. Dr. Weiland’s research interests include retinal prostheses, neural prostheses, electrode technology, visual evoked responses, and implantable electrical systems. He is a member of the IEEE EMBS, the Biomedical Engineering Society, Sigma Xi, and the Association for Research in Vision and Ophthalmology.