Macular Degeneration & Care
Macular degeneration, also known as age-related macular degeneration (AMD) is a common condition in older adults and the leading cause of vision loss and blindness in people over the age of 65. Macular degeneration affects the macula, the part of the retina responsible for the crisp, detailed vision needed for reading or driving.
Although macular degeneration reduces vision in the central part of the retina, it does not affect the eye’s side or peripheral vision. For example, you could see the outline of a clock but not be able to tell what time it is.
Fortunately, macular degeneration alone does not result in total blindness, since peripheral vision is not affected. Even in advanced cases, people continue to have some useful vision and often are able to take care of themselves. In less severe cases, the impact on vision and lifestyle may be minimal.
Macular degeneration (AMD) can be classified as either ‘wet’ (neovascular or exudative) or ‘dry’ (atrophic):
- Dry macular degeneration is more common and usually less severe than the wet type. This type of AMD usually develops as a result of aging and thinning of the macula.
- The ‘wet’ form of AMD accounts for 10% of all cases. Abnormal blood vessels develop beneath the retina and cause leakage of blood and fluid into the macula. This leakage leads to permanent damage to the macula resulting in blurred central vision. Vision loss may be rapid and severe.
Patients with macular degeneration may notice gradual changes to their vision, including shadowy areas in the central vision, or fuzzy and distorted vision. These areas grow larger as the disease progresses, and can eventually turn into blind spots. Patients may also have difficulty seeing fine details and straight lines may appear wavy or distorted. Sometimes only one eye loses vision while the other continues to see well for years.
With wet macular degeneration, central vision loss can occur rapidly, sometimes in as little as a few days or weeks.
Your doctor may be able to detect early signs of macular degeneration during a comprehensive eye exam.
Causes & Risk Factors
The exact causes of macular degeneration are not fully understood, although aging and genetics appear to play a role. Nearly half of cases of severe AMD appear to be inherited.
Macular degeneration is most common in Caucasian women. The risk for all patients increases with age beginning in one’s 60’s. Over 14% of adults between the ages of 70 and 79 have been diagnosed with advanced or intermediate age-related macular degeneration.
Other factors that may increase your risk of macular degeneration include:
- High fat diet
- Prolonged sun exposure
Patients can minimize their risk of macular degeneration by practicing a healthy, active lifestyle and getting regular comprehensive eye exams.
Although the exact causes of macular degeneration are not fully understood, antioxidant vitamins and zinc may reduce the impact of AMD in some people. A large multi-center government-sponsored study (AREDS) found that people at risk for developing advanced AMD lowered their risk by 25% when treated with a combination of vitamins C, E, beta carotene and zinc. It is not yet known if these supplements lessen the incidence in people in lower risk categories or in family members of affected individuals.
It is very important to understand that these vitamin supplements are not a cure and will not restore vision lost from AMD. You should speak with your ophthalmologist to determine your need for vitamin supplementation and the specific products recommended. We suggest that the patient also check with his or her primary care physician to insure that there are no troublesome interactions with other medications.
Treatments for the wet type of macular degeneration include laser surgery and intraocular injections of Avastin or Lucentis. These drugs are often successful in stopping abnormal blood vessel growth in wet macular degeneration. These FDA-approved medications are injected into the vitreous of the eye on a monthly basis to control the damaging effects of wet macular degeneration. The injections are painless and safe with a low complication rate.
In those individuals with significant vision loss, a wide array of devices is available to assist people in continuing their favorite activities. Our Low Vision specialist, Dr. Starr is specially trained and state-certified in the prescribing of devices including magnifiers, closed-circuit television, large-print reading materials and talking or computerized devices.