Dry macular degeneration is the more common variation of age-related macular degeneration (AMD). It happens when important tissue in a person's eye begins to deteriorate, leading to gradual vision loss. Usually, people who have this disorder will see a blind spot in the middle of their visual range. The disorder progresses rather slowly, and there is usually no real discomfort associated with it. Over time, it can develop into a much more severe disorder called wet macular degeneration, which causes bleeding from the eyes and is associated with much more severe vision loss.
In the early stages, dry macular degeneration may show up as a difficulty seeing in dark areas. This may get worse until a person's vision starts to become hazy or blurry. Eventually, there will be a noticeable blind spot developing in center of the eye, along with a blurry area around the blind spot. It is not uncommon for one eye to degenerate much faster than the other, and as long as one eye is asymptomatic, it may not have a huge effect on a person's lifestyle.
Certain patients may experience visual hallucinations. This problem is known as Charles Bonnet syndrome, and the cause is unknown. People may only see geometric shapes, or they may see complex images like buildings and people. Some scientists think this is caused by the brain trying to make up for a lack of visual input, but there hasn't been very much research into the subject. Those who suffer from this symptom can often keep it to themselves because they're afraid others will think they're losing their sanity.
Other than the general association with aging, there is very little information about a cause for dry macular degeneration. Some risk factors have been discovered, including smoking, high blood pressure, and lighter eye color. The disease also seems to have a genetic component, and if a person has a relative with the disorder, his risk is increased significantly. In terms of demographics, Caucasians and females tend to have a significantly higher chance of developing the disorder.
There is no actual cure for dry macular degeneration, but some studies show that progression can be slowed with certain nutritional changes. Beta-carotene and vitamins E and C have all been associated with a slowed progression. There is also evidence that people who eat more of these nutrients may have a lesser chance of ever developing dry macular degeneration. Some of this evidence is still being studied, but early results are generally considered promising by most doctors.