What is Macular Degeneration
Macular degeneration is an accumulation of deposits in the retina that causes loss of function of the specific portion of the retina used for central vision (the macula). This causes difficulty with activities such as reading, driving, and recognizing faces. The macula is a highly specialized area of the retina which is 100 times more sensitive to detail that the rest of the retina and is responsible for color discrimination. Even in its most severe form, macular degeneration will not cause total blindness as it does affect peripheral (side) vision, so people can lead independent lives in familiar environments.
Macular degeneration has two basic forms: wet and dry. The dry form is much more common, encompassing about 90% of people with macular degeneration, and typically causes a gradual decrease in vision most noticeable when reading. It almost always occurs in both eyes, but may be worse in one eye. Once a patient has been diagnosed with dry macular degeneration, it may remain dry or can undergo a sudden change to the wet form. Wet macular degeneration occurs when blood (or fluid from blood vessels) enters the macula and damages the sensitive retinal tissue. The blood comes through a barrier layer behind the retina that breaks down as a result of the process of macular degeneration. Exactly why some eyes convert to wet macular degeneration is not know; however, there is often a subtle change in the vision that may serve as a warning sign. It is important to diagnose and treat wet macular degeneration as soon as possible in hopes of preserving the best vision possible.
What are the Risk Factors?
Age is the biggest risk factor for macular degeneration. It is very unlikely in people under the age of 50, while it is the leading cause of blindness in Americans over the age of 55. Racial differences also play a large role in the likelihood of macular degeneration. The condition is far more likely to occur in Caucasians and rare in African-American, Asians, and Hispanics. The two main risks factors that you can control are smoking and sun exposure. Long-term exposure to UV light from the sun’s rays increases the risk of developing macular degeneration. The effects of UV exposure seem to be cumulative over the years, so high quality sunglasses with UVA and UVB protection is recommended. Cigarette smoking also increases the risk of developing macular degeneration. Like sun exposure, the effects of smoking are cumulative and even being a former smoker can put you at a higher risk.
How is it Diagnosed?
Most patients will notice a gradual loss of focusing ability, but many have no symptoms in the early stages of the disease. Occasionally, visual changes such as distortion of straight lines, missing areas of central vision or fuzzy areas may be seen. Since these symptoms also occur in conditions such as cataracts or retinal disease, a comprehensive examination of your eyes is necessary. In the wet form of the condition, a dramatic change in the vision occurs very rapidly in the affected eye.
The diagnosis is made by one of our optometrists after examining your eyes following dilation of the pupils. The macula undergoes characteristic changes in appearance that lead to the diagnosis of macular degeneration. The examination will also allow us to determine whether you have the dry or wet type. Photographs and/or retinal scans are often used to monitor progression through time.
How is it Prevented?
A diet rich in dark leafy green vegetables (spinach, kale, collard greens, etc)and bright colored vegetables (bell peppers, tomatoes, carrots) is important in protecting the sensitive macula. Sun protection with UVA and UVB sunglasses is imperative to prevent sun damage that can lead to macular degeneration.
How is it Treated?
The treatment for macular degeneration depends on whether the condition is wet or dry. For the dry type of macular degeneration, vitamins containing antioxidants and/or carotenoids are beneficial in slowing the progression of dry macular degeneration. Depending on the degree of macular damage, your doctor may recommend AREDS 2 (containing lutein and zeaxanthin) and/or omega 3 supplements with can help reduce progression. In wet macular degeneration, intraocular injections and/or laser surgery may be necessary to help partially restore lost vision and prevent further progression.