Age Related Macular Degeneration – Georgia Eye Institute
Age related Macular degeneration (AMD) is a leading cause of vision loss in those over 65. The associated anxiety of losing vision and independence can best be addressed with an understanding of the person at risk, the symptoms, and the treatments that improve the prognosis if the diagnosis is made early.
Macular degeneration is group of conditions that causes the central part of the retina, the macula, to lose the ability to see. This is an area behind the eye that cannot be easily seen or evaluated unless the eyes are dilated. There are two types of macular degeneration, wet and dry.
Dry macular degeneration is much more common and involves a slow process of aging cells that stop working and lead to blurred or missing areas in the central field of vision. It does not take away side vision.
Wet macular degeneration occurs when the aging retina grows new blood vessels that leak fluid and cause bleeding under the retina. These changes under the retina lead to sudden symptoms of blurred central vision and demand a prompt evaluation and treatment by an Optometrist.
It is much less common than dry AMD but receives more attention because of the potential for sudden severe loss of vision and because treatment is available. Patients are often ill prepared for the effect to lifestyle, hobbies, and work.
Macular degeneration helps improve the prognosis, but it is very important to understand that early macular degeneration often has no symptoms. Therefore, nothing replaces regular dilated eye exams and the American Academy of Ophthalmology suggests an exam every one to two years after the age of 65.
Patients must remain vigilant by testing each eye alone for more advanced symptoms: blurred vision, distortion, or missing areas in the central vision. The patient may notice it is more difficult to see faces or read, but it is important to remember that with both eyes open, advancing macular degeneration in one eye can be missed.
One can avoid this by checking vision with one eye covered while reading the paper or doing a Sudoku puzzle. Symptoms such as bent/curved lines, or missing letters can be noticed with single corrective eye exam.
Monitoring your vision is good at all ages but from a practical standpoint we can use our personal risk factors to guide our frequency of monitoring for symptoms. While we recognize an increased risk in blue eyed Caucasians of northern European descent, there is three risk factors that demand greater attention: a positive family history, a history of past or present smoking, and advancing age. Every race has an increased risk with advancing age, but a family history can be the most predictive. Genetic testing is not recommended yet but patient with a positive family history of AMD requires earlier and more frequent exams to identify early disease and to allay unnecessary fears if the exam is normal.
While you can’t pick your genetics or stop aging, smoking is the most important risk factor that you can modify. If you are concerned about vision loss from AMD, you must stop smoking. After your dilated macular exam, you and your doctor can tailor a reasonable frequency for exams and home monitoring for advancing AMD.
If monitoring detects new distortion, blurred vision, or areas of missing vision, you should seek prompt consultation with your eye doctor. Early diagnosis is important because it improves prognosis. Diagnostic evaluations may be as simple as a dilated retinal exam with your doctor but could also include an optical coherence tomography (OCT).
This is a retinal scan that can detect small amounts of retinal fluid that may otherwise be missed. More advanced testing with a retina specialist may include an injection of a contrast agent into your arm to perform an angiogram of the retinal vessels to look for abnormal new vessels. These tests determine your potential need for treatment.
Treatment of wet AMD has seen great strides over the past 10 years. The prognosis has greatly improved with the introduction of injectable medication. Patients who were once certain to become blind have a much better chance of maintaining useful vision.
The importance of early treatment is highlighted by the 90% of people who will maintain or have improved vision if injection treatment is started during early onset of the disease. Regular injections of Eylea, Lucentis, or off- label use of compounded Avastin suppresses leakage and bleeding but unfortunately does not cure the disease. While a few patients can stop therapy, most require regular monitoring and injections indefinitely.
There is no current treatment for dry macular degeneration, but research is looking for ways to stop the degenerative process. Most therapy is supportive in nature with low vision aids to help with reading and daily tasks. Low vision aids can also be of great help to patients with wet AMD.
Vitamin therapy is based on the Age Related Eye Disease Studies that evaluated the role of high dose vitamin therapy at reducing the incidence of AMD and vision loss. In the AREDS II trial, those patients taking the supplements with lutein/zeaxanthin had a 26% reduced risk of developing advanced AMD compared to those not taking the supplement. Most of the participants also took a multivitamin.
Macular degeneration is a complex topic that can cause anxiety because it is poorly understood, and we all fear the loss of vision and independence. With education, routine monitoring, and prompt therapy, the poor vision, and fear of AMD can be minimized.
We stress regular dilated eye exams, not smoking, and a diet in green leafy vegetables and AREDS II vitamin supplements to reduce its effect.