Many of you probably know someone who is affected by age-related macular degeneration (AMD). Many people have a mild form of it and function well, while others have suffered significant vision loss. AMD affects millions of people worldwide and is the leading cause of vision loss in Americans age 60 and older. The damage caused by macular degeneration cannot be reversed, and one's age and genetic makeup are the most significant risk factors for developing AMD. Recently, there have been a few updates in the treatment and prevention of AMD that I'd like to share with you.

The macula is the central and most sensitive part of the retina, and corresponds to the portion of our eyesight we use to look at things with fine detail. Age-related macular degeneration is a chronic disease that occurs when the tissue in the macula deteriorates and therefore, makes it difficult for us to read, drive and recognize faces.

Macular degeneration is divided into two forms-"dry" and "wet."

Dry AMD

Dry AMD is characterized by the degeneration of certain retinal layers with a subsequent increase in the amount of cellular waste products. As these waste products accumulate, the nutritional supply to the retina is disrupted and the healthy retinal cells eventually begin to deteriorate. Most people have the dry form of AMD. The vision loss is often mild to moderate; so many people can lead a very fulfilling life.

Wet AMD

Wet AMD almost always begins as dry AMD. Wet AMD accounts for 10-15 percent of all cases, but it is responsible for most of the severe vision loss people experience. Wet AMD develops when new blood vessels grow from underneath the retina. Unfortunately, these vessels leak fluid or blood that cause distortion of the retina and significant vision loss.

A few years ago, the results for the first arm of the Age-Related Eye Disease Study (AREDS) were published. The AREDS trial is an ongoing study that is monitoring a large number of people with various stages of macular degeneration. The study has shown that specific doses of antioxidants and zinc can help reduce the risk of developing advanced macular degeneration by 25 percent. Ask your doctor if the AREDS formula is right for you.

Better options for those with "Wet" AMD

Until recently, little could be done to treat those with wet AMD. One of the very first treatments for wet AMD was laser photocoagulation. This is when high-energy lasers were used to create small burns in the areas of the abnormal vessels with hopes that the leaking vessels would be cauterized and destroyed. Unfortunately, this treatment also destroyed healthy tissues around the vessels inherently causing some vision loss. Only a very small percentage of people were candidates for this procedure, and the results were often disappointing.

A subsequent development in laser treatments is Visudyne with Photodynamic Therapy (PDT). This is a cool-beam laser that is used with a light-sensitive drug to specifically target abnormal vessels in the eye. PDT is also intended to seal off the leaking vessels, however PDT does not damage the healthy surrounding tissue. This has all but replaced laser photocoagulation. Although this treatment provides better results than photocoagulation, only a select few individuals actually qualify for this treatment.

Lucentis and Macugen are recently developed treatments that limit the growth of leaky abnormal vessels. Clinical trials showed that a significant number of people who received this treatment had their condition stabilized, and, in fact, some even realized an improvement in their vision. Currently, there is a great deal of research devoted to finding new ways to prevent blood vessels from growing and leaking.

Some recommendations to reduce your risk of developing AMD are to wear UV protective sunglasses, quit smoking and eat a healthy, balanced diet rich in fruits and vegetables.

I am encouraged by these recent developments, and I am hopeful that future therapies will help an even greater number of those with macular degeneration. Early detection and intervention is imperative in order to get the most out of these treatments, as they provide limited help to those with advanced disease or who have had wet AMD for some time. It is recommended to have your eyes examined promptly if you experience blurred or distorted vision.

David J. Weis, O.D. is a comprehensive eye care specialist at Milwaukee Eye Care Associates. For an appointment call 414-271-2020.