What Is Age-Related Macular Degeneration (ARMD)?
Age-related macular degeneration (ARMD or AMD) is the leading cause of severe, permanent vision loss in people over age 60. It happens when the small central portion of your retina, called the macula, wears down. The retina is the light-sensing nerve tissue at the back of your eye.
Causes of Macular Degeneration:
Age-related macular degeneration is more common in older people above 50 years Those with family history are at much higher risk Other risk factors include Smoking, having high blood pressure or high cholesterol, obesity, eating diet rich in saturated fat, being light-skinned, Caucasian, being female, and having a light eye color.
Symptoms of Macular Degeneration:
AMD doesn’t cause complete blindness. Early on, you might not have any noticeable symptoms. It might not be diagnosed until it gets worse or affects both eyes
- Dark, blurry areas in the centre of your vision. Over time, this blurry area may get bigger or you may see blank spots. Things may also seem less bright than before.
- Losing your central vision can make it harder to see faces, drive, or do close-up work like cooking.
- But your peripheral (side) vision will still be normal. For instance, imagine you are looking at a clock with hands. With AMD, you might see the clock’s numbers but not the hands.
- Some people may also notice that straight lines start to look wavy. This can be a warning sign for late AMD.
lf you have any of these symptoms, go to an eye doctor as soon as possible
Wet vs. Dry Macular Degeneration :
There are two main types of ARMD:
- Dry ARMD: This form is quite common (90%). People with this may have yellow deposits, called drusen, in their macula. A few small drusen may not cause changes in your vision. But as they get bigger and more numerous, they might dim or distort your vision, especially when you read. As the condition gets worse, the light-sensitive cells in your macula get thinner and eventually die. In the atrophic form, you might lose central vision.
- Wet ARMD: This form is rare (10%), but serious. Abnormal blood vessels grow from underneath your macula. These blood vessels leak blood and fluid into your retina and form Choroidal Neovascularisation membrane (CNVM). Your vision is distorted so that straight lines look wavy. You may also have blind spots and loss of central vision. These blood vessels eventually form a scar, leading to permanent loss of central vision.
How Is Macular Degeneration Diagnosed?
Eye doctors can check for AMD as part of a comprehensive dilated eye exam. The exam is simple and painless — your doctor will give you some eye drops to dilate (widen) your pupil and then check your eyes for AMD and other eye problems.
If your doctor dilates your pupils, your vision may be blurry and sensitive to light for a few hours after the exam. It’s a good idea to ask a friend or family member to drive you home — especially if you’ve never had a dilated eye exam before.
One of the most common early signs is drusen (tiny yellow spots under your retina) or pigment clumping.
Your doctor can see these when they examine your eyes Your doctor may also ask you to look at an Amsler grid, a pattern of straight lines that resembles a checkerboard. Some of the straight lines may appear wavy to you, or you may notice that some of the lines are missing. This grid helps you notice any blurry, distorted, or blank spots in your field of vision. These can be signs of macular degeneration.
Your doctor may also recommend doing a test called an optical coherence tomogram (OCT). This test will take scans of the retina of your eye with a special machine and provides very detailed images of the macula. The machine won’t touch your eye.
Your doctor may do fluorescein angiography to see what is happening with your retina. Yellow dye (called fluorescein) is injected into a vein, usually in your arm. A special camera takes photos of the retina as the dye travels throughout its blood vessels. If there are new vessels or vessels leaking fluid or blood in your macula, the photos will show their exact location and type.
It’s important to see your eye doctor regularly to find signs of macular degeneration early. Treatment can slow the condition or make it less severe.
What Treatments Are Available for Macular Degeneration?
There’s no cure for macular degeneration. There’s currently no treatment for early AMD, so your eye doctor will probably just keep track of how your eyes are doing with regular eye exams. Having Advanced AMD in one eye puts you at higher risk of developing late AMD in your other eye.
Eating healthy diet, regular exercise, and quitting smoking will help. Treatment may slow it down or prevent further loss. Your options include:
- Anti-angiogenesis drugs (Anti-VEGF injections): Aflibercept(Eylea), and Ranibizumab (Accentrix/ Razumab) — prevent formation of abnormal blood vessels and leaking from these vessels. Many patients who were administered these injections got back vision that was lost. You need to have this injections multiple times. This injection is delivered to your eye through a very slender needle.
- Low vision aids: These are devices that have special lenses like magnifying tools, or electronic systems like handheld computers to create larger images of nearby things. They help people who have central vision loss from macular degeneration to make the most of their remaining visual field.
- Rehabilitation (training) programs: to help you learn how to use your side vision to help you do things.
- If you have macular degeneration, you will need regular eye exams for close monitoring.
Macular Degeneration Prevention
You may be able to lower your risk of AMD (or slow its progression) by making these healthy choices:
- Quit smoking
- Regular physical activity
- Normal blood pressure and cholesterol levels
- A large study found that some people with dry AMD could slow the disease by taking supplements of vitamins C and E, lutein, zeaxanthin, zinc, and copper. Ask your eye doctor about these supplements.
Testing Your Vision with the Amsler Grid :
You should use an Amsler grid regularly to monitor your vision. One is below for you to use.
Here is how to use the Amsler grid:
- Keep the Amsler grid in a place where you see it every day (for eg) on their refrigerator/bathroom door. Disciform scar
- In good light, look at the grid from about 12–15 inches away. Be sure to wear your reading glasses if you normally use them.
- Cover one eye. Look directly at the dot in the center of the grid with your uncovered eye. Notice if any of the lines look bent or wavy. See if any part of the grid looks blurry, dim, or is missed or out of shape.
- Now cover your other eye and test your vision similarly again
Call your ophthalmologist right away if you notice that any lines or parts of the grid look wavy, blurry, or dim.