Signs And Symptoms Of Age Related Macular Degeneration

Macular degeneration usually develops gradually and painlessly. The signs and symptoms of the disease may vary, depending on the type of macular degeneration you have.

Signs And Symptoms Of Age Related Macular Degeneration

With dry macular degeneration you may notice the following symptoms:

• The need for increasingly bright illumination when reading or doing close work
• Printed words that appear increasingly blurry
• Colors that seem washed out and dull 
• A gradual increase in the haziness of your overall vision 
• A blind spot in the center of your visual field combined with a profound drop in your central vision 

With wet macular degeneration, the following symptoms may appear rapidly:

• Visual distortions, such as straight lines appearing wavy or crooked (a doorway or street sign that seems out of whack) 
• Decreased central vision
• A central blurry spot 

In either form of macular degeneration, your vision may falter in one eye while the other remains fine for years. You may not notice any or much change because your good eye compensates for the weak one. It's when the condition develops in both eyes that your vision and lifestyle are dramatically affected.

Causes 

Generally speaking, macular degeneration involves a breakdown in the system that provides nourishment to and removes waste from the macula. Although this breakdown often accompanies a deterioration of the RPE, the reasons why the system stops working are poorly understood. The disease is likely triggered by a combination of several factors.
 
Dry macular degeneration
 
Dry macular degeneration is the result of a deterioration of the retinal pigment epithelium brought on by aging. The light-sensitive cells of the macula continuously shed used-up outer segments as waste. This waste is broken down and disposed of by the RPE into the choroid. At the same time, cones and rods continuously produce new outer segments to replace the discarded ones.
 
When you develop dry macular degeneration, the waste disposal system falls apart. Aging slows the process to a point where waste starts to accumulate in the RPE. This accumulation interferes with the normal function of the RPE, causing the light-sensitive ceils of the macula to degenerate.
 
The appearance of mottled pigmentation and drusen - which are clumps of waste deposit - signals this development. The appearance of small drusen can be common as you age and does not interfere with vision, but large drusen with indistinct edges are often associated with a decrease in vision.
 
Wet macular degeneration
 
In wet macular degeneration, abnormal blood vessels grow from the choroid underneath the retinal pigment epithelium. This is called choroidal neovascularization (CNV). Think of tree roots growing under a sidewalk and lifting it up. These abnormal blood vessels may leak fluid and blood, lifting up the RPE and the macula in blisters or bumps. This damages the light-sensitive cells of the macula. Eventually the abnormal blood vessels transform into scar tissue, creating a permanent blind spot in the center of your vision.

Much like the dry form of macular degeneration, a breakdown in the waste removal system may be what's causing the CNV. When the waste from the cones and rods is not disposed of and begins to accumulate, sufficient flow of nutrients to the macula is interrupted.

The abnormal growth of blood vessels may be a response to this interruption in the flow of nutrients. And without enough nutrients, healthy tissue in the macula begins to deteriorate.
 
Risk factors 

Researchers may not know the exact causes of macular degeneration, but they have identified some contributing factors. They include:

• Age
• Race
• Sex 
• Light-colored eyes 
• A family history of macular degeneration 
• Long-term exposure to ultraviolet light and blue light (the wavelength just above ultraviolet), which includes sunlamps as well as regular sunlight 
• Low blood levels of minerals and antioxidant vitamins, such as A, C and E 
• Cigarette smoking 
• Cardiovascular disease - for example, circulatory problems, stroke, heart attack, angina 

Age and race figure prominently in the development of macular degeneration. In the United States the disease is most common in whites over age 50. It affects about 11 percent of whites ages 65 to 74, and 28 percent of whites age 75 and older. Macular degeneration is less common in blacks, Asian-Americans and American Indians than it is in other groups.

Signs And Symptoms Of Age Related Macular Degeneration

Having a family history of macular degeneration is perhaps the greatest risk factor. Women are more likely than are men to develop macular degeneration and, because they tend to live longer, to suffer the effects of severe vision loss from the disease.

Exposure to environmental pollution - especially cigarette smoke - greatly increases your risk. Smokers are two to three times more likely to develop macular degeneration than are nonsmokers. To find out more, you can check out Signs And Symptoms Of Age Related Macular Degeneration.