by Kimberly Allen R.N.
Macular degeneration is a medical condition that occurs when a portion of the eye know as the macula deteriorates causing vision problems. It is estimated that over 2 million Americans are affected by macular degeneration and the numbers are climbing with expectations of over 3 million by the year 2020. The reason for the increase is the aging population. Macular degeneration is almost always age related (AMD) affecting people over 50 years old. It is the number one cause of legal blindness in people over 55 years old in the US alone.
There is no exact cause for AMD documented, however , it is believed to be mostly genetic though there is some evidence that environmental factors also play a role. There are also several known risk factors. Next to age is family history as those with the highest risk of developing AMD. Other risk factors include race – AMD is more common in whites and lightly pigmented people including those with lighter eye color. Women seem to be at a greater risk than men. Another factor seems to be long term exposure to sunlight, for example having worked outside or any other activity that includes repeated exposure to UV rays.
There are 2 types of macular degeneration:
1. Dry AMD occurs gradually resulting at the tissue that covers the retina begins to deteriorate getting thinner. When this tissue deteriorates it is no longer able to efficiently exchange the nutrients and waste products, therefore the waste products begin to build up and form small deposits. As the waste deposits continue to accumulate the light cells in the retina become damaged.
2. Wet AMD begins the same way as dry AMD, however in wet AMD tiny new blood vessels start growing under the area in the back of the eye known as the macula. What causes the blood vessels to grow is unknown, but it is believed they grow in an attempt to help the retina remove the waste products. These blood vessels frequently leak blood into the eye. The symptoms of wet AMD can be more severe than those of dry AMD.
The symptoms of AMD vary depending on the type of AMD present. In dry AMD, it can take years before you notice the symptoms. Some of the symptoms you may experience with dry AMD include; needing a brighter light when reading, colors appear dull and your vision may be hazy, less defined, you may even have trouble recognizing faces. In wet AMD, the symptoms appear more suddenly than with dry AMD. The central vision becomes blurred and there are some visual distortions like straight lines looking wavey and a blind spot usually develops in the center of the visual field. The blind spot will continue to grow when left untreated.
There is research in progress searching for a cure, however, currently there is no cure for dry AMD. As dry AMD progresses very slowly, the deterioration of vision is also very slow. It is the central zone of vision that is affected, not the peripheral, so people with dry AMD do not go completely blind. However, they usually need magnifying lenses, large print books, and brighter lights to improve and maintain quality of life. There has also been a study that proved using dietary supplements containing high doses of zinc and antioxidants significantly inhibit the natural deterioration of dry AMD.
Wet AMD is more serious and has a greater potential to cause significant loss of vision. There are several treatments currently available to manage the symptoms and reduce significant loss of vision. The most common is known as photodynamic therapy (PDT). It has been approved by the FDA as safe and effective. In PDT, a medication called verteporfin is given to the patient through an IV. Verteporfin is a medication that is specific for identifying the abnormal blood vessels in the eye. Then a very mild laser beam is introduced to the eye that destroys only the abnormal blood vessels while leaving the normal ones untouched. This prevents the abnormal blood vessels from leaking into the eye.
According to retinal experts, all patients with AMD wether wet or dry should be taking supplements high in zinc and antioxidants.
There are other treatments available, but not every patient will qualify for certain treatments with the exception of supplements. There are certain criteria that must be met depending on the treatment. Your doctor will be able to explain to you what treatments you “qualify” for depending on the severity and location of the blood vessels. Many treatments need to be repeated so it’s important to discuss your options with your doctor.
Kimberly Allen is a registered nurse with an AND in nursing. She has worked in ACF, LCF and psychiatric facilities, although she spent most of her career as a home health expert. She is now a regular contributor to HealthAndFitnessTalk.com, dispensing advice and knowledge about medical issues and questions. You can reach her with any comments or questions at firstname.lastname@example.org.