Age-Related Macular Degeneration Treatment with Laser Coagulation
When new blood vessel growth is not found directly under the fovea, a standard treatment for neovascular AMD is coagulation of the blood vessels with a laser. This procedure, called photocoagulation, is noninvasive and performed on an outpatient basis by an ophthalmologist with special training and experience.
Before the 15- to 20-minute procedure, the eye is dilated with eyedrops and anesthetized with drops or an injection. The doctor then aims a high-energy laser beam at the new blood vessels to destroy them.
According to the Macular Photocoagulation Study, the procedure decreases the risk of vision loss when well-defined new blood vessels can be identified in extrafoveal, juxtafoveal, or subfoveal sites. For example, in study participants with extrafoveal AMD, severe vision loss occurred after 18 months in 60 percent of untreated eyes but in only 25 percent of treated eyes.
The risk of severe vision loss was also lowered after photocoagulation of juxtafoveal and subfoveal vessels. Although benefits of photocoagulation lasted five years, they did diminish over time. After successful photocoagulation, neovascularization recurred in 10 percent of patients after one to two months, 24 percent after six months, and 54 percent after three years.
Because of this high rate of recurrence, anyone who has the procedure needs to be carefully monitored, periodically undergoing fluorescein angiography. If new symptoms of vision loss or distortion appear, an immediate examination is needed. A close watch must be maintained on the other eye as well. Some people use an Amsler grid for self-monitoring; however, this is not particularly reliable.
One potential complication of photocoagulation is damage to the macula, which can result in a permanent blind spot in the center of the visual field. This complication occurs most commonly in people with neovascularization close to or at the center of the macula.