Macular Degeneration

What is age-related macular degeneration?

Also called AMD, age-related macular degeneration is a common eye disease associated with aging that gradually destroys sharp, central vision. For some people, AMD advances so slowly that it will have little effect on their vision as they age. For others, the disease progresses faster and may lead to a loss of vision in one or both eyes.

There are two types of AMD:

• Dry AMD – 90% of all people with AMD have this type. Scientists are still not sure what causes dry AMD. Studies suggest that an area of the retina becomes diseased, leading to the slow breakdown of the light-sensing cells in the macula (the part of the eye where sharp, straight ahead vision occurs) and gradual loss of central vision.
• Wet AMD – Although only 10% of all people with AMD have this type, it accounts for 90% of all blindness from this disease. As dry AMD worsens, new blood vessels may begin to grow and cause “wet” AMD. Because these new blood vessels tend to be very fragile, they will often leak blood and fluid under the macula. This causes rapid damage to the macula that can lead to the loss of central vision in a short period of time.

Who is at risk for AMD?

The greatest risk factor for macular degeneration is age. Although it may occur during middle age, people over the age of 60 are at a much greater risk than other age groups. Other macular degeneration risk factors include:

• Gender – Women tend to be at a greater risk for AMD than men.
• Race – Caucasians are much more likely to lose vision from AMD than African Americans.
• Smoking – Smoking can increase the risk of AMD.
• Family history – Those with immediate family members who have AMD are at a higher risk of developing the disease.

What are the symptoms of AMD?

Both dry and wet AMD cause no pain. The most common early sign of AMD is blurred vision. Often, this blurred vision will go away in brighter light, but if the loss of light-sensing cells increases, people may see a growing blind spot in the middle of their field of vision.

The classic early symptom of wet AMD is that straight lines appear crooked. This happens when fluid from leaking blood vessels gathers and lifts the macula, distorting vision. A small blind spot may also appear in wet AMD, resulting in a loss of central vision.

How is AMD detected?

AMD might be suspected if you are over the age of 60 and have had recent changes in your central vision. To look for signs of the disease, eye drops will be used to dilate your pupils for a better view of the back of your eye. You may also be asked to look at an Amsler grid, a pattern that looks like a checkerboard, to see if it appears distorted, which is a sign of AMD.

Your Nethery Eye Associate physician can help coordinate treatment of wet AMD with monthly injections of medications called VEGF inhibitors, which reduce the growth of abnormal blood vessels, slow their leakage and help slow vision loss. These injections can be spread farther apart as the patient responds to the treatment.