Blurred Lines and Other Symptoms of Macular Degeneration
Macular Degeneration Affects Many
The Centers for Disease Control and Prevention report that 1.8 million people over the age of 40 are affected by macular degeneration. With the aging of the baby boom generation, it is estimated that 2.95 million people will have age-related macular degeneration (AMD) by 2020.
AMD occurs when the macula, the central part of the retina, is damaged. This leads to a loss of central vision, as well as loss of sight close-up or in fine detail.
There are two forms of AMD: dry macular degeneration and wet macular degeneration. Both can lead to permanent impairment of reading and fine detail vision.
Wet Versus Dry
Dry AMD is the more common form of macular degeneration. An estimated 70 to 90 percent of all AMD cases are the dry form. In dry AMD, the retina, which is the thin layer of tissue at the back of the eyeball, starts to deteriorate. The macula is at the center of the retina. The macula begins to thin and break down, leading to fuzziness in the center of your field of vision.
Wet AMD is more severe, and progresses more rapidly than dry AMD. In wet AMD, blood vessels at the back of the eye begin to leak fluid or blood into the macula.
Risk Factors for AMD
The cause of AMD is unknown, but AMD is highly genetic. Certain genes account for approximately 70 percent of the risk for the condition.
AMD is most common in people over 65, and Caucasians are most likely to be at risk. Risk factors for developing dry AMD include smoking, being overweight, eating an unhealthy diet, cardiovascular disease, and high cholesterol.
Having dry AMD, drusen, and/or systemic inflammation increases the risk of developing wet AMD.
An early marker of the risk of AMD is the formation of drusen in your retina. Drusen can be seen at the back of the eye during dilation in an eye exam.
Drusen are small white or yellow fatty protein deposits in a membrane within your retina. Some drusen are small, hard, and far apart—this type of drusen is less likely to indicate AMD. If drusen are soft, closer together, and larger, you may have a greater risk of developing wet AMD and more severe vision loss.
If your eye doctor finds drusen in your retina, they may want you to come in for more frequent eye exams.
Dry AMD Symptoms
Dry AMD symptoms come on gradually. One or both eyes may be affected. You may not really notice the problem until you have an eye exam.
You may find that you need brighter light in order to read. Entering a dimly lit room may take you some time to adjust your vision.
Words on the page may become more blurry. It can become harder to recognize faces, and color may become less distinct.
Generally your central vision becomes hazier, and possibly “crooked.” In advanced macular degeneration, you may see hallucination of geometric shapes or even people.
Three stages of Dry AMD
The National Eye Institute defines three stages of dry AMD:
- Early AMD: Small drusen or a few medium drusen are present. Little vision loss or symptoms are detectable.
- Intermediate AMD: Many medium drusen or a few large drusen are present. Some people still experience no symptoms, but some begin to have a blurred spot in the center of their vision. You may start to notice that you need more light to read clearly.
- Advanced dry AMD: More large drusen are present. Within the macula, the light-sensitive cells begin to breakdown. This causes a blurred spot in the center of your vision. This spot can get larger and larger within your forward-facing vision.
Wet AMD Symptoms
The dry form of AMD can turn into the wet form at any stage. Abnormal blood vessels grow under the macula and leak blood. The resulting swelling damages the macula and the retina.
In the early stages of wet AMD, straight lines can appear wavy. A grid is often used for diagnosis, because in looking at a grid, the twisting or waviness of lines is very apparent to the afflicted patient.
In wet AMD, many of the same symptoms as dry AMD can occur, with blurred vision and the need for bright light to read. Onset of symptoms is often faster, and progression can be rapid.
Substantial vision loss with wet AMD can occur quickly, so getting prompt treatment to slow down progression is very important.
Your Doctor Can Help
Macular degeneration can be frightening. Losing your vision is a threat no one wants to face. But with prompt treatment and assistive technologies, you can preserve your vision and lead a full life, even with vision loss.
See your doctor promptly if you note any vision changes. Dry AMD may be slowed with a combination of vitamins including vitamin C, E, A, zinc and copper. Dietary changes, such as a low-fat diet, and treating diabetes and heart disease may be beneficial for AMD symptoms. Omega-3 supplements may help with inflammation.
Wet AMD may be treated with drugs to slow the growth of blood vessels. Surgery may help improve vision with implantation of special lenses.
Assistive technologies like magnifiers and audio systems can help you cope with vision loss.
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