Retinitis pigmentosa (RP) affects about 1 in 3,500 people worldwide. Age-related macular degeneration affects as many as 1 in 4 people by the age of 75 and is the leading cause of blindness in people over age 50 in the United States. Both RP and AMD have a hereditary basis, and currently, there is no cure for either of these types of hereditary retinal degeneration. My clinical specialty is diagnosing and caring for patients with these diseases, using modalities from fluorescein angiography, to optical coherence tomography (OCT), to electroretinography (ERG).
In both RP and AMD, loss of vision is a result of photoreceptor cell degeneration and death. Treatments that can prevent photoreceptor degeneration in experimental models of retinal degenerations may have utility in preventing degeneration in both RP and AMD. I am interested in investigating novel treatments to preserve retinal function in patients with RP, cone rod dystrophy, Stargardt disease, Best disease and AMD.
Patients with rod specific defects undergo degeneration not only of rods, but also of cone photoreceptors. Because cones are responsible for fine visual acuity and color perception, their degeneration is particularly disabling for patients. I am interested in studying the relationship between cone photoreceptor survival and rod-specific gene defects in hereditary retinal degenerations, with the goal of preserving visual function mediated by both rods and cones.
A major challenge in the study of retinal degenerations lies in the fact that the cells affected by these diseases, the photoreceptors and retinal pigment epithelial (RPE) cells, are not visible in the eyes of living people. My collaborator Dr. Austin Roorda at the UC Berkeley School of Optometry has developed a novel device, the adaptive optics scanning laser ophthalmoscope (AOSLO), with the ability to image individual cone photoreceptors in the central retina of living eyes. We have studied cones in patients with RP, cone-rod dystrophy and other types of retinal degeneration to better understand why vision is lost in these diseases. See Dr. Roorda’s laboratory webpage for additional details about this research.
The UCSF Retinal Degenerations Clinic participated in 3 multi-center clinical trials for patients with inherited retinal degenerations. Two Phase II/III clinical trials evaluated the effect that a growth factor called ciliary neurotrophic factor (CNTF) has on retinal function in patients with early and late stages of RP. A Phase I study evaluated the safety and efficacy of a new generation epiretinal prosthetic device to stimulate visual perception in patients with end-stage RP. These clinical trials are among the first to study possible treatments for patients with these blinding diseases.