The device is called a Scanning Laser Ophthalmo-scope and it allows eye doctors to measure the effects of glaucoma more simply and accurately than ever before. Glaucoma is characterized by excess pressure within the eye that may damage the optic nerve to the point where vision becomes impaired. The scanning laser ophthalmoscope has shown promise in detecting changes in the optic nerve even before there is damage to vision.
"We know that the key to controlling glaucoma is to catch it early," said Mary Lynch, associate professor of ophthalmology at the School of Medicine. "We hope the laser ophthalmoscope will allow us to do just that."
During an examination, a pinpoint of infrared laser light is directed across the retinal surface in the back of the patient's eye. Reflected light is measured as the laser scans 32 minuscule planes of retinal tissue, and a computer uses more than 1 million bits of information gathered to generate telling images of the optic nerve head. Within minutes, colorful three-dimensional images are available on a video screen, and two-dimensional images are available on paper. The procedure requires only that patients keep an eye open for one and a half seconds. No dilating eye drops are required.
Until now, the primary diagnostic tools for measuring glaucoma have been the visual field exam and ophthalmic photography. While the visual field exam is an excellent indicator of visual impairment caused by glaucoma, it can detect the presence of glaucoma only after the optic nerve has become involved.
The disadvantages of taking photographs of the eye are the time involved and the use of dilating drops, both challenges when photographing children with glaucoma. The laser ophthalmoscope is far superior to either of these conventional tests in detecting the subtle clues to glaucoma's presence.
"Emory glaucoma specialists Reay Brown, Allen Beck and I are enthusiastic about applying this new laser technology to glaucoma research and screening," Lynch said. "For instance, we hope to scan the eyes of a large number of persons without glaucoma to create a database of normal eyes against which the computer may compare patients' eyes."
The group also would like to apply laser ophthalmoscope technology to screening for glaucoma in high risk groups.
-- Lorri Preston