Age-Related Macular Degeneration Overview
At Retina Center of Arkansas, we aim to treat our patients and educate them on any other valuable information that can help them feel more comfortable. According to the NIH, 11 million Americans suffer from age-related macular generation. Below is some information from board-certified ophthalmologist and fellowship-trained vitreoretinal microsurgeon Dr. DellaCroce that could help those suffering from this alignment.
What is Macular Degeneration?
The macula is the part of the retina in the back of the eye that gives us our central vision. It is where light focuses when we are looking directly at something. It is what allows us to see detail (reading, recognizing faces, seeing fine detail).
Age-Related Macular Degeneration is a weakening or deterioration of the macula that occurs in adults over 50 years of age. In this older group of adults, it is the leading cause of vision loss.
Macular degeneration is classified as dry or wet. Most people with AMD have the dry form (about 80%). Wet AMD is less common but more serious. Macular degeneration usually starts out as the dry form, and in about 20% of patients with Dry AMD it can progress to Wet AMD.
Dry Macular Degeneration
Dry Macular Degeneration is usually a slow deterioration of the macula that occurs over the years. Parts of the macula get thinner or atrophy with age, and tiny clumps of protein called drusen can form under the retina. Vision loss is often slow (over years), and initially, there may be no symptoms. As it progresses, it can lead to a loss of clarity and contrast in vision and some mild distortion.
Wet Macular Degeneration
Macular Degeneration is classified as “Wet” when abnormal blood vessels form and begin to grow beneath the macula; it usually happens in patients that already have Dry AMD. These blood vessels usually leak fluid and blood underneath the retina and cause scarring of the macula if left untreated. Once the macula has become scarred from this process, it can lead to permanent damage to the central vision.
Symptoms of Macular Degeneration
Macular Degeneration may not have any noticeable symptoms in the early or milder stages. As dry macular degeneration progresses, there may be a loss of brightness and contrast in vision. As Dry AMD progresses or the early stages of Wet AMD begin, straight lines and edges (window frames, lines on the highway) may begin to look bent or wavy. The most accurate way to self-check these symptoms is to use an Amsler Grid. If you have a diagnosis of AMD, it is important to monitor your eyesight. If there are changes in vision, you should notify your retina specialist or eye doctor promptly.
Macular Degeneration Diagnosis
An eye doctor will perform a dilated eye exam to assess for signs of AMD. A scan with an optical coherence tomography machine (OCT) allows a very detailed image of the macula to assess for AMD. It is a common way to follow the progression of the condition and response to treatment.
Other methods of evaluation may include fluorescein angiography, where a special dye is injected into a vein in the patient’s arm or hand. The dye travels through the blood vessels, and a special camera can image the dye as it moves through the blood vessels of the eye. This can show if abnormal blood vessels are growing under the macula.
Optical coherence tomography angiography (OCTA) is another way to look closely at the blood vessels in and under the macula. It is similar to fluorescein angiography but does not require the use of a dye.
Treatment for Macular Degeneration
There is no cure for AMD. The most recent Age-Related Eye Disease Study (AREDS2) demonstrated a 26% reduced risk of progression to advanced AMD compared to those not taking supplements by taking a vitamin formula containing the following:
- Vitamin C (500mg)
- Vitamin E (400 IU)
- Lutein (10 mg)
- Zeaxanthin (2 mg)
- Zinc (80 mg)
- Copper (2 mg)
The AREDS2 formula is not a replacement for a daily multivitamin, and most participants in the studies continued their daily multivitamin along with the AREDS2 supplements. Examples of the AREDS2 vitamins commonly found in supermarkets or drug stores are brands such as I-Caps, Preservision, and Ocuvite. There are many other brands available; one should make sure that when buying an eye supplement that it follows the AREDS2 formula.
Dark-green leafy vegetables, yellow fruits and vegetables, fish, and a balanced nutrient-rich diet have been shown to reduce the risk of developing significant AMD, but it is difficult to achieve the recommended levels of lutein and zeaxanthin through diet alone.
Treatment for Wet AMD
When AMD progresses to the Wet form, the most effective treatment is to treat the condition with anti-Vascular Endothelial Growth Factor (anti-VEGF) medications. These drugs block the formation of abnormal blood vessels and leakage from blood vessels in the eye that cause Wet Macular Degeneration. Examples of the available drugs currently used to treat Wet AMD are Avastin, Lucentis, Eylea, and Beovu.
Although these drugs can be very effective at slowing, stopping, and reversing Wet AMD and improving and stabilizing patient’s vision, their effects can wear off over time. Initially, it is recommended to treat patients with a monthly injection until the Wet AMD has stabilized. Most retina specialists employ a treatment regimen that involves extending the time between injections based on the stability of the patient (treat and extend).
Prognosis for Wet AMD
Unfortunately, it is very common for Wet AMD to come back after stopping treatment longer than 2-3 months, and some patients may require long-term maintenance to keep Wet AMD from coming back.
If the patient appears stable enough to discontinue treatment, regular follow-up is important, and monitoring of vision by the patient with an Amsler Grid helps to identify any early signs of relapse. The danger in the condition flaring up is that scar tissue can form, which cannot be reversed.
Ongoing research is aimed at treating the disease on a genetic level and with drugs for Wet AMD that have a longer duration of effect, allowing less frequent treatment. Hopefully, as more progress is made, we will have a cure for AMD.