Laser photocoagulation for age-related macular degeneration
Laser photocoagulation is a type of laser surgery that uses an intense beam of light to burn small areas of the retina and the abnormal blood vessels beneath the macula. (See a picture of the eye.) The burns form scar tissue that seals the blood vessels, keeping them from leaking under the macula. By sealing the leaky blood vessels, laser photocoagulation slows down:
- The buildup of fluid under the retina that distorts the shape and position of the macula.
- The growth of scar tissue and the abnormal membrane under the retina, both of which damage the cells in the macula.
- Central vision loss.
Laser surgery may be done in a doctor's office or eye clinic using a local anesthetic that affects only the eye area. The surgery itself is painless. But your eye may hurt slightly after the surgery.
What To Expect After Surgery
Laser photocoagulation does not involve a hospital stay. You will need someone to pick you up at the doctor's office or clinic. Your pupils will be widened (dilated) for the surgery. And they will remain dilated for several hours. Wear sunglasses to keep bright light out of your eyes while they are dilated.
Your vision may be blurry. And your eye may hurt a little for a day or two after the surgery.
Why It Is Done
The surgery works best when the abnormal blood vessels (choroidal neovascularization) are clustered close together in a specific area. Blood vessels that are scattered over a wider area are much harder to treat. Surgery is also less helpful after the abnormal blood vessels reach the center of the macula (fovea).
Your doctor will decide whether you might benefit from treatment by finding the exact location of the abnormal blood vessels and scar tissue using a fluorescein angiogram.
How Well It Works
Laser surgery will not restore vision that has already been lost because of macular degeneration. But it can sometimes slow down or delay further damage to a person's central vision. The growth of fragile new blood vessels in wet AMD recurs in about half of people within 3 years after surgery.2 Even repeated treatment is not usually effective over the long term in preventing some loss of central vision.
You will return for follow-up exams to make sure that the blood vessels have not started to leak again. At home, check for changes in your vision by using an Amsler grid.
Laser surgery burns and destroys part of the macula. This often results in some central vision loss (a blind spot, or scotoma, where the laser created a scar). This vision loss is usually unavoidable.
What To Think About
The most serious drawback to laser surgery is that the laser damages some of the nerve cells in the macula that react to light. This causes some vision loss. Sometimes the vision loss that could result from surgery is just as bad as or worse than the vision loss that could result from not treating the eye. But in other cases, laser surgery may make vision worse at first but prevent more severe loss of vision over time.
Your doctor will help you weigh the risks and benefits of laser surgery based on your history, the results of your exams and tests, and his or her own experience in treating the disease.
There is a great deal of interest in whether laser photocoagulation of drusen in people with dry AMD may help prevent severe vision loss. Drusen are yellowish white deposits that build up under the retina. The evidence from research is conflicting. Some evidence shows that laser treatment may eliminate drusen and decrease the rate of severe vision loss after 2 years. But there is also some evidence that this treatment may actually trigger the growth of abnormal blood vessels (choroidal neovascularization), which causes wet AMD.2 This potential treatment for dry AMD is still being studied.
Last Updated: August 4, 2009
Author: Jeannette Curtis