Age related macular degeneration
Age-Related Macular Degeneration (AMD) is one of the most common causes of vision loss and blindness in Australia. AMD is a retinal eye disease that causes progressive loss of central vision, but leaves the peripheral vision intact. This progressive degeneration affects the macula, which is responsible for fine detail and colour. This can make it difficult to read, drive, write, recognise faces, or perform daily tasks.
AMD can be divided into two general types: Dry (Atrophic) and Wet (Exudative). The “dry” form of AMD results from a slow wearing away of the layers of the macula, and occurs over many years. As dry AMD progresses, you may notice a central blurring in your vision. The “wet” form of AMD is due to leakage of blood or fluid from an abnormal blood vessel that grows in the macula. This can lead to sudden distortion or loss of central vision in a short period of time. Wet AMD is responsible for the majority of cases of severe vision loss in AMD.
The risk of AMD increases as a person gets older. New studies have shown that people over the age of sixty are a greater risk than any other group. Other AMD risks include smoking, gender (females more likely to get AMD than males), and cholesterol. People with a family history of AMD may be at higher risk of getting AMD. Recently, studies have also shown that high cholesterol levels have been linked with a higher risk for wet AMD.
Currently there is no treatment for dry AMD. However, there are various ways to help slow down the progression of macular degeneration. These include:
- Cessation of smoking
- Control of cholesterol and blood pressure levels
- Increase intake of fish and other omega rich foods
- Eat a diet rich in fresh fruit and green, leafy vegetables
- Wear ultraviolet protection when outdoors
- Monitor vision with Amsler grid
- Routine comprehensive vision exams as recommended by your optometrist or ophthalmologist
Much recent research has been done regarding treatment options for wet AMD, and these studies have revealed that Lucentis has been the most effective and beneficial treatment. Lucentis has been proven to prevent vision from getting worse and a small percentage of Lucentis patients noted an improvement in their vision. However, not everyone is a candidate for Lucentis. There are other treatments available which include Visudyne therapy, thermal laser treatment, and Avastin injections. Your ophthalmologist will provide a treatment plan that best works for your eyes.
There is also the availability of low vision aids which amplify your vision to help you get along with your everyday life. These devices include hand magnifiers (with light), stand magnifiers, telescopes (for face and street sign recognition), binoculars, and or CCTV (which allows you to stick your reading material under a screen, which magnifies the reading material for you). For more information on low vision options, please ask your optometrist or ophthalmologist.
Above: Fluorescein angiogram image. The image on the top is normal, the image on the bottom shows wet AMD.
Below: OCT image of a normal macula.
OCT image of dry form of AMD
OCT image of wet form of AMD