Macular degeneration is an eye condition commonly associated with aging. The condition is essentially what its name infers: The macula in your eye begins to break down and disintegrate. The condition is irreversible and can lead to total blindness. What is most concerning is that this condition often begins with little or no detectable symptoms. As time progresses, symptoms may increase and can include an over sensitivity to bright light, or blurry vision.
What is the Macula?
The macula is located at the center of the retina, and is responsible for our central, high resolution vision that allows us to see fine detail in our direct line of sight. We use our macula to read, recognize faces, or watch television. We use other sections of our retina to provide our side vision, or the ability to see at night.
Age-Related Macular Degeneration
There are many types of macular degeneration (AMD). The most common type is Age-related AMD, for which Caucasians over age 50 are most at-risk. Age related AMD is known as “dry” AMD, where the breakdown of a person’s sharp central vision it advances slowly and progresses through three specific stages. People suffering the effects of dry AMD do not notice a diminishment in their vision at first. A more aggressive form of AMD is known as “Wet" age-related macular degeneration. The wet form of AMD progresses quickly and causes more severe vision loss.
What is Dry Age-Related Macular Degeneration?
The "dry" form of macular degeneration is often diagnosed by an x-ray that shows the presence of yellow fatty deposits, called drusen, located under the eye retina. A few small drusen may not cause changes in vision, but as time passes and the drusen multiply, they begin to block oxygen-rich nutrients from reaching the retina. This interference with the macula causes the retina to decline. Soon, color and central vision become affected. Dry AMD often begins with one eye, but can lead to the other eye becoming affected.
The Three Stages of Dry Macular Degeneration
Dry AMD slowly progresses through three stages:
- Early – Patient has no symptoms or vision loss. Small amounts of yellow drusen are visible when viewed by an ocular x-ray.
- Intermediate – The patient may require more light for reading, and may notice small, blurred spots in the center of their vision. A regression in light-sensitive cells and supporting tissue in the central retinal area begins to progress. As time goes on, the blurred spot may increase in size and appear darker.
- Advanced – In the advanced stages of dry AMD, approximately 10% of people develop wet macular degeneration. The blurred spot in the center of vision becomes so large that it is hard to recognize faces.
What is Wet Age-Related Macular Degeneration?
Wet AMD progresses faster than dry AMD and most often leads to more significant vision loss. Wet AMD refers to eye blood vessels that, for reasons unknown, become abnormal and begin to leak fluid and blood from blood vessels located in the back portion of the eye. When the fluid is released, it raises the macula from its regular position. Unfortunately, this condition can progress rapidly. Central vision begins to blur and progresses to blindness.
What Causes Macular Degeneration?
While the cause of AMD is unknown, there are certain risk factors that can contribute to the development of age-related macular degeneration. The most common risk is age, where AMD is mostly commonly found in individuals over 50 years old. Additional risks include a family history of AMD, obesity, smoking, high blood pressure, elevated cholesterol, and a diet low in fruits and vegetables. Long exposure to harmful UVA sunlight is also a culprit.
Can Sunglasses or Contacts Help To Prevent Macular Degeneration?
Protecting your eyes from damaging UVA Light is important for eye health. When choosing protective eyewear, sunglasses that are labeled as providing 100% UVA protection are describing their ability to block UVA rays from the front surface of the eyeglass lens.
Researchers now know that up to 50% of UVA light that can damage vision, entering our eyes from the side of our face and even from behind our head, where the sunlight can reflect off the back of our sunglass lens into the eye. Wraparound sunglass styles that are designed to block the light from the top, bottom, and sides of our face are more effective than sunglass styles that only offer frontal lens protection.
Additionally, some contact lenses containing UV-blocking agents, like Acuvue, can enhance eye protection; however, while they will cover your cornea, they do not protect the white portion of the eye. UV protecting contacts are designed to complement sunglasses, and are not to be used as a substitute. As the UV-blocking agent present in contact lenses is clear and barely visible, read the contacts package label to determine if your lenses contain a UV- blocker, or ask your eye care professional,.