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Media Contact: Michael Schwartzberg, Media Relations Manager GBMC Physician Completes Groundbreaking Research On Advanced Dry Age-Related Macular Degeneration BALTIMORE, Md. – November 8, 2006 – Results of the largest study of advanced dry age-related macular degeneration (AMD) to date have found that baseline measure of visual function can predict visual loss two years later. Janet Sunness, M.D. a National Institutes of Health funded-researcher and a retina and low vision specialist at the Greater Baltimore Medical Center, conducted the study of geographic atrophy between 1992 and 2000 as a faculty member of the Wilmer Eye Institute at the Johns Hopkins University School of Medicine. Dr. Sunness, Medical Director of Richard E. Hoover Rehabilitation Services for Low Vision and Blindness at GBMC, and an international authority on vision issues, measured visual acuity of 131 patients with normal chart illumination, and again when the chart illumination was dimmed using a moderate filter, such as a sunglass. The worsening of vision in dim lighting was a strong predictor of subsequent visual acuity loss, a measure that holds promise as an early detector of the effectiveness of therapy for dry macular degeneration. Dr. Sunness found that those patients who worsened by four or more lines on the visual acuity chart with the filter in place were 2.7 times more likely to lose vision over the next two years than those patients who worsened by less than four lines. This study has provided most of the current knowledge of the progression and visual function characteristics of AMD, for which there is no treatment at the present time. AMD is the leading cause of visual impairment for people age 50 and older. Dr. Sunness is presenting results of the study November 12 at the American Academy of Ophthalmology Annual Conference in a presentation titled “Visual Function in Dim Illumination is a Strong Predictor of Subsequent Visual Acuity Loss in Advanced Dry AMD.” “A simple test, the low luminance deficit, had high predictive value for the subsequent loss of vision in these patients,” explained Dr. Sunness. The results are notable, she said, because it means that patients at highest risk for visual loss can be identified, which would allow for smaller sample sizes and less follow-up time required for future clinical trials for treating this disorder. Additionally, it suggests that this measure can be used as a way of screening drugs and other potential therapies for their likelihood of succeeding at treating geographic atrophy. “Drugs may be able to improve vision under dim illumination, long before the two years it would take to have an obvious impact on the progression of visual loss, so that they may be used as surrogate outcomes for clinical trials,” Dr. Sunness said. “This could potentially allow short screening trials of medications, with those that succeed being the ones tested for longer term trials.” Dr. Sunness found that 40% of eyes with geographic atrophy and good visual acuity at baseline worsened by three or more lines of visual acuity at two years of follow-up, a rate higher than the visual loss caused by diabetic eye disease, long regarded as a major public health problem. Twenty-seven percent of these eyes with geographic atrophy and good acuity at baseline were legally blind by four years of follow-up. Patients enrolled in the study received annual examinations and median follow-up was over four years. There are two types of AMD that lead to severe central visual loss: The ‘wet’ type, the growth of new blood vessels under the retina that cause leaking of fluid and blood and scarring of the central retina, which has been widely studied, and the advanced ‘dry’ type, in which there is a dropout of retinal cells, leading to blind areas in the central vision, has been less recognized and less studied. An ophthalmologist by training, Dr. Sunness is a leading world expert on geographic atrophy, the advanced ‘dry’ type of AMD, which is present in 3.5% of people age 75 and over in the United States and increases in prevalence with age to involve about 25% of people age 90 and over. It generally involves both eyes, and causes blind areas in the central field of vision. It progresses gradually over time, with blind areas often developing near but not initially involving the fovea, the very center of the macula. These blind areas enlarge and coalesce over time, becoming horseshoe-shaped and then ring-shaped blind areas surrounding but still sparing the fovea. Eventually, the fovea too becomes blind and the patient’s visual acuity drops to the legal blindness level. While there is still some sparing of the fovea, the patient may have relatively good vision when reading single letters, but may have great difficulty with reading words or recognizing faces because the full word or full face does not ‘fit’ within the small spared area that is surrounded by a blind area. These patient also need a great deal of light in order to see, and their vision drops dramatically in dim environments such as restaurants, or when they come inside after being outdoors on a sunny day. A resident of Pikesville, Dr. Sunness’ clinical practice focuses on low vision and on retinal and macular disease. She joined GBMC in March 2005. Prior, she spent 21 years with the Johns Hopkins medical system, including serving as an associate professor in the School of Medicine’s Department of Ophthalmology for the past nine years, as well as serving as medical director of the Low Vision Service, director of the Retinal Dystrophy Center and director of the Visual Function Service, all at the Wilmer Ophthalmological Institute. The Richard E. Hoover Rehabilitation Services for Low Vision & Blindness was established in 1986 at GBMC as a joint venture with the Maryland School for the Blind and the Hoover family. Dr. Hoover led the hospital’s Ophthalmology Department for a quarter century, and had a long history of service as a teacher, ophthalmologist, and board member at the Maryland School for the Blind. Dr. Hoover dedicated much of his career to developing rehabilitation programs for visually impaired people. These services, which bear his name, continue this mission of teaching people the skills they need to function each day despite impaired sight. High-technology devices can be useful to some patients with low vision or blindness. GBMC’s Hoover Vision Information & Education Works (VIEW), located on the 3rd floor of Physician’s Pavilion West, showcases the latest technology such as closed circuit televisions for the visually impaired. Patients and family can examine and "test drive" a multitude of devices to evaluate and compare their usefulness. VIEW also offers both optical aids such as high-powered magnifiers, telescopes or electronic devices, and & non-optical aids such as check writing guides, bold tip pens, yellow acetate filters, talking watches and clocks, large button phones and large playing cards.About GBMC ###
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