High resolution fluorescence imaging with adaptive optics
David R. Williams
This talk will describe a scanning laser ophthalmoscope that combines adaptive optics, confocal imaging, eye motion correction, and fluorescence methods to image mosaics of cells in the living primate eye with 2 micron transverse resolution. For example, the instrument can provide simultaneous images of the mosaic of cone photoreceptors and of retinal pigment epithelial (RPE) cells. Subcellular features can be resolved in single RPE cells. This imaging technique may eventually help track the progression of age-related macular degeneration as well as the efficacy of therapy for this increasingly prevalent disease. More superficial layers in the retina than the cones have been more difficult to image due to their obligate transparency. Nonetheless, fluorescence labeling methods including the retrograde transport of rhodamine dextran injected into the LGN and intravitreal injections of AAV designed to cause retinal cells to express GFP now make it possible to image individual ganglion cells in living monkey eyes, including subcellular structures such as axons and dendrites. These methods may have important applications in the study of glaucoma, which causes ganglion cell death. They may also eventually lead to the ability to optically monitor or control the neural responses of hundreds of retinal neurons simultaneously, which could clarify the roles of the many morphologically distinct retinal neurons whose function is currently unknown.
David Williams, Ph.D.
William G. Allyn Professor of Medical Optics
Center for Visual Science and The Institute Of Optics
University Of Rochester
Dr. Williams received his BS from Denison University in 1975, his Ph.D. from the University of California, San Diego in 1979. He was a postdoctoral fellow at Bell Laboratories, Murray Hill in 1980 and joined the University of Rochester in 1981, where he has an appointment in the Institute of Optics as well as in the departments of Brain and Cognitive Sciences, Biomedical Engineering, and Ophthalmology. He is currently William G. Allyn Professor of Medical Optics. Since 1991, Williams has served as Director of Rochester’s Center for Visual Science, an interdisciplinary research program of 30 faculty interested in the mechanisms of human vision. Williams’ research marshals optical technology to address questions about the fundamental limits of spatial and color vision. His research team demonstrated the first adaptive optics system for the eye, showing that vision can be improved beyond that provided by conventional spectacles. His team also showed that adaptive optics can provide microscopic images of the retina with unprecedented resolution. He is a Fellow of the Optical Society of America, the American Association for the Advancement of Science, and the Association for Research in Vision and Ophthalmology. He received the OSA Edgar G. Tillyer Award in 1998, and the Archie Mahan Prize in 2004. He is also the 2006 recipient of the Association for Research in Vision and Ophthalmology’s Friedenwald Award and the 2007 recipient of the Bressler Prize from the Jewish Guild for the Blind.