What is Age-related Macular Degeneration (AMD)?
- AMD is a common eye condition and a leading cause of vision loss among people age 50 and older
- It causes damage to the macula, a small spot near the center of the retina and the part of the eye needed for sharp, central vision, which lets us see objects that are straight ahead.
- The condition can make it difficult to read or recognize faces.
What are the risk factors for developing AMD?
What are the symptoms of AMD?
- Blurring of central vision (may be gradual or rapid in onset)
- Increasing difficulty with reading
- Patchy visual loss
- Distorted vision e.g. a grid of straight lines appears wavy and parts of the grid appear blank
What are the two types of AMD?
Generally, patients with AMD are grouped into one of two categories – those with dry macular degeneration (Dry AMD) and those with wet macular degeneration (wet AMD).
Dry AMD
- About 80% (8 out of 10) of people who have AMD have the dry form which is quite common
- Dry AMD is when parts of the macula get thinner with age and tiny clumps of lipoprotein called drusen grow and you slowly lose central vision
- As Dry AMD progresses, blurred spot is seen in the center of the vision
- There is no way to treat dry AMD yet
Wet AMD
- This form is less common, affecting only 10 percent of all people with AMD but is much more serious
- Wet AMD is when new, abnormal blood vessels grow under the retina. These vessels may leak blood or other fluids, causing scarring of the macula
- You lose vision faster with wet AMD than with dry AMD.
How is AMD diagnosed?
The early and intermediate stages of AMD usually start without symptoms. Only a comprehensive dilated eye exam can detect AMD. The eye exam may include the following:
Visual acuity test
This eye chart measures how well you see at distances
Dilated eye exam
Your eye care professional places drops in your eyes to widen or dilate the pupils. This provides a better view of the back of your eye. Using a special magnifying lens, he or she then looks at your retina and optic nerve for signs of AMD and other eye problems.
Amsler grid
Your eye care professional also may ask you to look at an Amsler grid. Changes in your central vision may cause the lines in the grid to disappear or appear wavy, a sign of AMD
Fluorescein Angiogram
In this test, which is performed by an ophthalmologist, a fluorescent dye is injected into your arm. Pictures are taken as the dye passes through the blood vessels in your eye. This makes it possible to see leaking blood vessels, which occur in a severe, rapidly progressive type of AMD (see below). In rare cases, complications to the injection can arise, from nausea to more severe allergic reactions.
Optical Coherence Tomography Angiography
OCT is a newer, non-invasive, quick exam that helps visualize the retinal microarchitecture. Sometimes, it will uncover tiny areas of fluid or retinal irregularity not readily apparent to a retina specialist during a microscopic exam.
Many people don’t realize they have AMD until their vision is very blurry. Therefore, it is important to have regular visits to an ophthalmologist. He or she can look for early signs of AMD before you have any vision problems
What are the treatment options for AMD?
Dry AMD
Currently, no treatment exists for Dry AMD, which in many people shows no symptoms or loss of vision. However, people with lots of drusen or serious vision loss might benefit from taking a certain combination of nutritional supplements.
- AREDS 2 (Age-Related Eye Disease Study 2) was a very large research study. It looked at taking vitamins and minerals daily for AMD
- This study found that certain nutritional supplements could help some people who have a lot of drusen
- These supplements may also help people who have lost a lot of vision in at least one eye from AMD
- It is important to remember that nutritional supplements are not a cure for AMD, but they may help to slow the disease in some people with early- to mid-stage AMD.
Wet AMD
Treatment options for wet AMD:
Laser Photocoagulation
Laser surgery may also be used to treat some types of wet AMD. Your eye surgeon shines a laser light beam on the abnormal blood vessels. This reduces the number of vessels and slows their leaking
Photodynamic therapy with verteporfin
This method uses a non-thermal laser together with an intravenous drug to seal and halt or slow the progression of the condition
Injections
To help treat wet AMD, there are medications called anti-VEGF drugs. Anti-VEGF treatment helps reduce the number of abnormal blood vessels in your retina. It also slows any leaking from blood vessels. This medicine is delivered to your eye through a very slender needle.
What Can I Do if I Have Already Lost Vision due to AMD?
Many people with AMD see better in bright light.
Paint rooms and ceilings in white to add extra brightness
Pull back curtains to allow more sun into the room
Choose the Right Light
What can I do to protect my vision?
5 Tips to Protect Against Macular Degeneration
References
- https://www.aao.org/eye-health/diseases/amd-macular-degeneration. Last accessed on 02/04/2019
- https://nei.nih.gov/health/maculardegen/armd_facts. Last accessed on 02/04/2019.
- http://www.northtexasretina.com/macular-degeneration.htm. Last accessed on 02/04/2019.
- https://www.singhealth.com.sg/patient-care/patient-education/age-related-macular-degenration. Last accessed on 02/04/2019.