Facts on Macular Degeneration

• Age-related macular degeneration is a common eye disease that causes deterioration of the macula, the central area of the retina, a paper-thin tissue at the back of the eye where light sensitive cells send visual signals to the brain. Sharp, clear, straight-ahead vision, color and fine detail are processed by the macula, and damage to this area results in blind spots and blurred or distorted vision. When the macula is damaged, many daily activities such as driving and reading become increasingly difficult.
  
  
• Age-related macular degeneration is a major cause of visual impairment in the U.S. Among Caucasians over age 65, it is the leading cause of legal blindness.
  
  
• Approximately 1.8 million Americans 40 years and older have advanced age-related macular degeneration, and another 7.3 million people with intermediate age-related macular degeneration are at substantial risk for vision loss.
  
  
• The government estimates that by 2020 there will be 2.9 million people with advanced age-related macular degeneration.
  
  
• It is estimated that the number of people with early age-related macular degeneration will double in the United States to more than 17.8 million by 2050.Without treatment, these patients would be expected to result in approximately 1.6 million cases of visual impairment or legal blindness compared to between 400,000 and 600,000 cases today.
  
  
• Age is a prominent risk factor for age-related macular degeneration. 3.8 percent of Americans between the ages of 50-59 have either intermediate or advanced age-related macular degeneration; by ages 70-79, this increases to 14.4 percent.
  
  
• Other risk factors include: smoking, family history of macular degeneration, gender, obesity, race, prolonged sun exposure, a high fat diet and/or one that is low in nutrients and antioxidants, hypertension, and cardiovascular disease
  
  
• There are two forms of macular degeneration: dry and wet.
  
  
• The dry form of macular degeneration, in which the light sensitive cells of the macula slowly break down, is the most common type, accounting for 90 percent of diagnosed cases.
  
  
• Wet macular degeneration accounts for approximately 10 percent of cases, but results in 90 percent of legal blindness. It is considered advanced macular degeneration (there is no early or intermediate stage of wet macular degeneration). Wet macular degeneration is always preceded by the dry form of the disease.
  
  
• It is possible for dry macular degeneration to advance and cause loss of vision without turning into the wet form of the disease; however, it is also possible for early-stage dry age-related macular degeneration to suddenly change into the wet form.
  
  
• To help diagnose macular degeneration, an eye care professional will perform a dilated eye exam, fundoscopy, a visual acuity test and fundus photography. If wet age-related macular degeneration is suspected, a fluorescein angiography, in which dye is used to detect leaking blood vessels, may also be performed. The patient may also be asked to look at an Amsler grid.
  
  
• Currently, there is no treatment or cure for advanced dry macular degeneration that will prevent vision loss. However, a specific high dose formula of antioxidant vitamins and zinc may delay or prevent intermediate macular degeneration from progressing to the advanced stage.
  
  
• Lucentis® (ranibizumab injection), Macugen® (pegaptanib sodium injection), laser photocoagulation and photodynamic therapy are some common treatments that can help control the abnormal blood vessel growth and bleeding in the macula for those with wet macular degeneration. Physicians have also used Avastin™ (bevacizumab injection), a cancer therapy manufactured by the company that makes Lucentis, as an “off-label” treatment for wet macular degeneration.
  
  
• Vision rehabilitation and low vision aids can help improve the quality of life for those who are visually impaired.
  
  
• A healthy lifestyle may help reduce the risk of developing macular degeneration. The following are recommended:
  
  
  • Don’t smoke
  • Exercise regularly
  • Keep blood pressure in a normal range and control other medical conditions
  • Maintain a healthy weight
  • Eat a diet high in fruits, vegetables and fish
  • Protect eyes from overexposure to sunlight with sunglasses and hats
    
    
• Ongoing research is exploring environmental, genetic and dietary factors that may contribute to macular degeneration. New treatment strategies are also being investigated, including retinal cell transplants, drugs to prevent or slow disease progress, radiation therapy, gene therapies, a computer chip implanted in the retina that may help simulate vision, and agents that will prevent new blood vessel growth under the macula.
  
  
• If you have been diagnosed with macular degeneration, don't be afraid to use your eyes for reading, watching TV, and other daily activities. Normal use of your eyes will not increase damage to your vision.

Source: Some of the information in this fact sheet was obtained from the National Eye Institute.

Last Reviewed On: 05/11/09