Macular Degeneration
Q: What is macular degeneration?
A: Macular degeneration is a deterioration or breakdown of the macula in the human eye that destroys sharp, central vision both near and far; vision that is necessary for seeing objects clearly and daily tasks such as reading and driving. The macula is located in the center of the retina at the back of our eyes. The retina is responsible for sending light impulses to the brain which are then translated into the images we see. When the macula does not function correctly, the impulses sent to the retina are hindered and the result is blurred, distorted or impaired central vision. Macular degeneration usually does not affect the eye’s side or peripheral vision and by itself does not result in total blindness.
Q: What causes macular degeneration?
A: The most common factor contributing to macular degeneration is age and this is referred to as age-related macular degeneration or AMD. Macular degeneration is the leading cause of severe vision loss in Caucasians over the age of 65 and generally women are more susceptible than men. Other risk factors for AMD include smoking, obesity, and family history however the exact causes of macular degeneration are unknown.
Another related factor of AMD is drusen. Drusen are yellow deposits that build up under the retina. The presence of a few small drusen is normal with age however the presence of larger or more numerous drusen in the macula is a common early sign of AMD.
Q: What are the types of macular degeneration?
A: DRY: This is the most common form of macular degeneration and occurs in 90% of the populace with AMD. The dry form involves a gradual breakdown of the light-sensitive cells in the macula and causes blurring central vision in the affected eye. Over time, central vision can deteriorate in one eye or both. The dry form can turn into the wet form, which is more vision threatening, but there is no way to tell how or if that will happen.
Wet: This form of macular degeneration occurs when abnormal blood vessels behind the retina start to grow under the macula. These blood vessels are very fragile and often leak blood and fluid that cause the macula to be lifted up from its normal position which creates distorted vision. The adverse effects of this process are rapid and the macula is quickly damaged. The wet type is known as advanced AMD and occurs in 10% of those with dry AMD.
Q: What are the symptoms of macular degeneration?
A: Macular degeneration can cause different symptoms in different people and it is important to note that there is no pain associated with either form. In fact, macular degeneration may hardly be noticeable in its early stages. Sometimes only the vision of one eye is affected while the other eye continues to see normally for many years. When both eyes are affected however, the loss of central vision may be noticed more quickly.
Dry: The most common early symptom of the dry form is blurred vision. As this form progresses, people will see details in front of them with less clarity and may have difficulty recognizing faces or reading. This blurred vision may go away with brighter light. Progressive symptoms can include a small but growing blind spot in the middle of one’s central vision.
Wet: The classic early symptom of this form is that straight lines appear wavy or crooked. The loss of central vision in this case is highly noticeable and happens quickly.
Q: How is AMD diagnosed?
A: While many people do not realize they have a macular problem until blurred vision becomes obvious, your OPI doctor can detect early stages of macular degeneration during a medical eye examination that includes the following:
- Visual acuity test
- Dilated eye exam
- Vision Test with an Amsler Grid
- Viewing the macula with an ophthalmoscope
- Taking special photographs of the eye such as fluorescein angiograms or optical coherence tomography, or OCT photos
A: While there is no proven way to prevent macular degeneration, one can reduce the risk of developing the disease with a healthy lifestyle – follow a diet that includes an abundance of green leafy vegetables and fish; do not smoke; maintain a healthy blood pressure and weight; and exercise.
Overall, the best treatment for macular degeneration is still early diagnosis. People over the age of 55 should have an annual dilated eye examination including an Amsler Grid Vision Test especially if they are experiencing any vision problems such as blurriness or loss of central vision.
Dry: Although the exact causes of macular degeneration are not known or fully understood, a major scientific study by the National Eye Institute found that taking a high-dose formulation of antioxidants and zinc may significantly reduce the risk of advanced AMD and its associated vision loss. It is important to understand that vitamin supplements are not a cure for AMD nor will they restore vision loss. Consult with your OPI doctor to determine if you are at risk for macular degeneration and to learn if supplements may be recommended for you.
Wet: There are several different types of treatment for the wet form of macula degeneration all of which are designed to control the growth of abnormal blood vessels behind the retina. These treatments include laser therapy, photodynamic therapy, macular translocation, or special anti-angiogenesis medicinal injections into the eye. Your OPI doctor can discuss with you the full range of treatment options for this form of macular degeneration and assist you in making the appropriate choice for your needs.
Q: What options are available to help with adapting to low vision that accompanies AMD?
A: Adapting to lower vision levels can be challenging but the good news is that there are a number of helpful options and support services to help you use your vision as effectively as possible and maintain an independent lifestyle. This includes low-vision optical devices such as magnifiers, closed-circuited television, large print reading materials and talking computerized devices. Talk with your OPI doctor about options, devices, and support facilities that are available in your area.
For more information, visit these websites:
www.aao.org, The American Academy of Ophthalmology
www.macular.org, The American Macular Degeneration Foundation
www.blindness.org, Foundation Fighting Blindness
www.nei.nih.gov/health/maculardegen/armd_facts.asp, National Eye Institute
