Age-Related Macular Degeneration

07/16/2015
Macular Degeneration.jpg

 

 

 

Age Related Macular Degeneration:
What Seniors & Caregivers Should Know

 

When a person’s vision begins to fail, it often happens so gradually that it’s difficult to know it’s even happening. One might question why the TV is blurry and blame it on the age of the TV. Or they might not be able to see the road while driving as well as they once did and assume their allergies are affecting their eyesight. Truth is; it could be age-related macular degeneration (AMD). If you’re a senior noticing changes in your vision, or a caregiver noticing your loved one straining to see, be sure to consult an eye doctor.

 

 

What is AMD?

AMD, a deterioration of the central portion of the eyes’ retina, is the leading cause of irreversible severe visual loss in the United States in people over 50 years of age. More than 8 million Americans have AMD, and the overall prevalence of advanced AMD is projected to increase by more than 50% by the year 2020. It causes damage to the macula, a small spot near the center of the retina and the part of the eye needed for sharp, central vision, which lets us see objects that are straight ahead.

 

In some people, AMD advances so slowly that vision loss does not occur for a long time. In others, the disease progresses faster and may lead to a loss of vision in one or both eyes. As AMD progresses, a blurred area near the center of vision is a common symptom. Over time, the blurred area may grow larger or you may develop blank spots in your central vision. Objects also may not appear to be as bright as they used to be.

 

AMD by itself does not lead to complete blindness. However, the loss of central vision in AMD can interfere with simple everyday activities, such as the ability to see faces, drive, read, write, or do close work, such as cooking or fixing things around the house.

 

The Macula

The macula is made up of millions of light-sensing cells that provide sharp, central vision. It is the most sensitive part of the retina, which is located at the back of the eye. The retina turns light into electrical signals and then sends these electrical signals through the optic nerve to the brain, where they are translated into the images we see. When the macula is damaged, the center of your field of view may appear blurry, distorted, or dark.

 

 

Who’s at risk?

Age is a major risk factor for AMD. The disease is most likely to occur after age 60, but it can occur earlier.

 

Other risk factors for AMD include:

 

  • Smoking. Research shows that smoking doubles the risk of AMD.
  • Race. AMD is more common among Caucasians than among African-Americans or Hispanics/Latinos.
  • Family history and Genetics. People with a family history of AMD are at higher risk. At last count, researchers had identified nearly 20 genes that can affect the risk of developing AMD. Many more genetic risk factors are suspected. You may see offers for genetic testing for AMD. Because AMD is influenced by so many genes plus environmental factors such as smoking and nutrition, there are currently no genetic tests that can diagnose AMD, or predict with certainty who will develop it.
    The American Academy of Ophthalmology currently recommends against routine genetic testing for AMD, and insurance generally does not cover such testing.

 

Does lifestyle make a difference?

 

Researchers have found links between AMD and some lifestyle choices, such as smoking. You might be able to reduce your risk of AMD or slow its progression by making these healthy choices:

 

  • Avoid smoking
  • Exercise regularly
  • Maintain normal blood pressure and cholesterol levels
  • Eat a healthy diet rich in green, leafy vegetables and fish

 

How is AMD detected?

The early and intermediate stages of AMD usually start without symptoms. Only a comprehensive dilated eye exam can detect AMD. The eye exam may include the following:

 

  • Visual acuity test. This eye chart measures how well you see at distances.
  • Dilated eye exam. Your eye care professional places drops in your eyes to widen or dilate the pupils. This provides a better view of the back of your eye. Using a special magnifying lens, he or she then looks at your retina and optic nerve for signs of AMD and other eye problems.
  • Amsler grid. Your eye care professional also may ask you to look at an Amsler grid. Changes in your central vision may cause the lines in the grid to disappear or appear wavy, a sign of AMD.
  • Fluorescein angiogram. In this test, which is performed by an ophthalmologist, a fluorescent dye is injected into your arm. Pictures are taken as the dye passes through the blood vessels in your eye. This makes it possible to see leaking blood vessels, which occur in a severe, rapidly progressive type of AMD. In rare cases, complications to the injection can arise, from nausea to more severe allergic reactions.
  • Optical coherence tomography. You have probably heard of ultrasound, which uses sound waves to capture images of living tissues. OCT is similar except that it uses light waves, and can achieve very high-resolution images of any tissues that can be penetrated by light—such as the eyes. After your eyes are dilated, you’ll be asked to place your head on a chin rest and hold still for several seconds while the images are obtained. The light beam is painless.

 

During the exam, your eye care professional will look for drusen, which are yellow deposits beneath the retina. Most people develop some very small drusen as a normal part of aging. The presence of medium-to-large drusen may indicate that you have AMD.

 

Another sign of AMD is the appearance of pigmentary changes under the retina. In addition to the pigmented cells in the iris (the colored part of the eye), there are pigmented cells beneath the retina. As these cells break down and release their pigment, your eye care professional may see dark clumps of released pigment and later, areas that are less pigmented. These changes will not affect your eye color.

 

Coping with AMD and vision loss can be a traumatic experience. This is especially true if you have just begun to lose your vision or have low vision. Having low vision means that even with regular glasses, contact lenses, medicine, or surgery, you find everyday tasks difficult to do. Reading the mail, shopping, cooking, and writing can all seem challenging.

However, help is available. You may not be able to restore your vision, but low vision services can help you make the most of what is remaining. You can continue enjoying friends, family, hobbies, and other interests just as you always have. The key is to not delay use of these services.