Macular Degeneration is among the most common causes of vision loss in people over 60 and is often called age-related macular degeneration (AMD or ARMD) for that reason. With that said, this disease can affect any mature adult, and screening should begin in your forties or if you have certain risk factors. As with many eye diseases, early detection and treatment is integral to maintaining vision and ensuring the best possible outcome.
The Inner Workings of Macular Degeneration
As light enters your eye through the clear, rounded cornea at the front of your eye, it is then focused onto the retina at the back of the eye. The retina then translates that light into a series of electrical signals that travel up the optic nerve and into your brain. In the center of the retina is a thin film known as the macula. This film is responsible for sharp, clear central vision. Macular degeneration comprises its ability to work properly, leading to vision changes and, eventually, loss.
Understanding the Types of Macular Degeneration
There are two primary types of macular degeneration, wet and dry. It’s possible to have both types at the same time, or to only have the condition in one eye.
Dry macular degeneration occurs when yellowish deposits called drusen form in the macula. A few small deposits may cause no symptoms at all, making early detection crucial. As the disease progresses, the drusen deposits grow in both size and number, which leads to distortion and dimming of vision over time. In later stages of the disease, dry macular degeneration thins the macula, which eventually causes the tissue to die. Spots of vision will be lost and, in the end stage, all central vision may be gone.
Wet macular degeneration is less-common than the dry form of the disease, but no less serious. In this form of the disease, abnormal blood vessels grow in the macula. This is called neovascularization. The blood vessels tend to leak blood and fluids into the retina, which causes a wavy visual distortion followed by spots of vision loss and central blindness.
Dry macular degeneration can lead to the wet form, with about 10 percent of patients affected. This section of patients comprises the vast majority of patients who experience serious vision loss. Most patients don’t progress to central blindness.
Determining Risk Factors
Lifestyle choices, diet and genetics are the primary factors that determine your risk of developing macular degeneration. While you can’t change your genetics, there are steps you can take with lifestyle and dietary choices to lower your risk.
High blood pressure and cholesterol levels are linked with AMD. To avoid these conditions, an active lifestyle with at least three workouts a week is crucial. Your diet also plays a part in staving off these conditions. Blood pressure can usually be controlled with a low-sodium diet, while cholesterol can be managed by limiting hydrogenated oils and transfats. Green, leafy vegetables, fish, nuts, seeds and low-fat dairy are all important to include in your diet, both for proper nutrients and to keep your blood pressure and cholesterol under control.
Obesity is also a huge risk factor for developing AMD, as well as many other diseases and conditions. If you are overweight, lowering your weight should be among your first priorities for your health. Speak to your doctor about diet changes, an exercise program and other support systems available to help you get your weight under control.
Smoking is a risk factor for developing macular degeneration, among other diseases. If you smoke and are having trouble quitting, smoking cessation programs and medications are available to help you. If you are not a smoker, limiting your exposure to smoke is also important. If your partner smokes and isn’t ready to quit, it may be time to add on a covered porch or vented sunroom to keep the cigarette smoke out of your living area. For more information, please see our comprehensive article on smoking and the effects on the eyes.
Genetics are another huge risk factor for AMD and are, unfortunately, unchangeable. Light-skinned females with light eye colors are most at risk, followed by those of Latino/Hispanic or African-American heritage. If your parents or grandparents developed AMD, you are at a higher risk than someone who has no family history of the disease. Researchers have discovered over twenty different genetic markers linked to AMD development, making routine genetic testing inadvisable. Genetics are simply one risk factor and cannot be relied upon definitively.
The First Notable Symptom
In the early stages of the disease, there are little to no symptoms of macular degeneration. As the disease progresses, patients may note wavy or distorted central vision. This is due to the changes happening in the retina and can occur in one or both eyes. Other than this, there are no symptoms, which is what makes this disease so dangerous to your vision. There is no pain or discomfort, no migraine headaches and no obvious signs of vision loss until the disease has progressed. It bears repeating that early detection is the one act you can take to protect yourself against significant vision loss.
Tests Used for Diagnosis
There are several different tests your optometrist or ophthalmologist use to detect eye disease, including macular degeneration. Most of them are done yearly, when you go in to have your eyeglass or contact lens prescription renewed. If you don’t wear corrective lenses, it’s still important to have a full exam every year or two, depending on your eye care professional’s recommendations.
The Amsler Grid. Your eyecare professional will show you a grid of lines that criss-cross, much like a checkerboard without any squares filled in. If you see distortion in the lines or there are holes in the grid, it’s possible you have macular degeneration. You can get a free Amsler Grid App here.
A visual acuity test. Not only does the eye chart test help your optometrist or ophthalmologist determine the proper prescription for you, it reveals any deficits in your central vision. You get get a free Vision test app here.
A dilated eye exam. Drops are placed in your eyes to make your pupils dilate. This allows your doctor to shine a light into your eyes and view the retina. He or she will then look for any signs of drusen forming, as well as any unusual blood vessels. This test doesn’t hurt, but it will make your vision blurry for an hour or two and you may need someone to drive you home. Don’t waive this test due to the inconvenience; it could save your sight.
A fluorescein angiogram. This test is done at the ophthalmologist’s office. Your optometrist will refer you to an ophthalmologist if he or she feels he test is warranted. A special dye is injected into your arm. As it flows through your body, the ophthalmologist will watch to see how the blood flow moves through your eyes. This will expose any unusual blood vessels and show whether they are leaking into the retina. The test is not painful, but there is always a risk that you may be allergic to the dye used. Talk to your doctor if you have allergies and are concerned; an allergy test can be performed with a smaller dose of the dye to see if you have an adverse reaction before performing the angiogram.
For dry macular degeneration, careful monitoring and supplements of beta-carotene, zinc, omega -3s and lutein are recommended. These supplements have been found to lower the chances of disease progression by 25 percent. In addition, these nutrients are also good for your cardiovascular health. Your doctor may also recommend dietary changes to pack in even more nutrients that support eye health, such as adding fish, avocados, nuts and green, leafy vegetables.
Wet macular degeneration can be treated with medications and injections that stop or slow the neovascularization, and there are also surgical procedures available to reduce the errant blood vessels. There is also a surgery available that places an implant in the eye and focuses light on a healthy portion of the macula, should such a portion exist. Your ophthalmologist will be able to advise you of your options, as every case is different and there is no one-size-fits-all solution.
Loss of Vision and Adaptation Strategies
If your disease has progressed and you’ve lost spots of vision or, in the more challenging scenario, lost central vision entirely, there are adaptation strategies and tools available to you to retain independence and allow you to carry on living as you did before your disease progressed.
Vision therapy, sometimes called vision rehabilitation, can help you sharpen your skills with using your remaining peripheral vision to navigate the world. This type of therapy is especially useful for those who have lost vision quickly with wet AMD and haven’t had time to adapt to the vision loss over time. Speak to your doctor about getting a referral to a visual therapist.
Low vision devices can help you retain independence and make life with low vision easier. Such devices include:
- Talking electronics, such as talking clocks, watches, cell phones and computers. These electronics are quite clever and some also respond to voice commands. You can learn to handle your banking, write an email or participate in online discussions, among other activities, by listening and responding to these devices.
- Magnification devices such as magnifying glasses and handheld video cameras that provide magnification can help you to see everyday correspondence, print books and small items on a larger scale.
- Large print editions are also available for many publications. Ordering these allows you to enjoy reading without sitting in front of your magnifier or listening. Portable and easy to use, large-print versions are available in a wide variety of genres and subjects. If you are a student, there are even large-print versions of many textbooks available.
- Psychological counseling is also a great idea for anyone experiencing vision loss. While some people can easily accept their condition, others may have unwanted emotions like unexplained rage, feelings of helplessness or being infantilized, despair and depression. It’s also normal and common to have deep anxiety about continuing in your relationships, passions, hobbies and career with a disability. A counselor can guide you through the process and help you develop coping strategies. There’s no shame at all in needing help; vision loss is a serious and upsetting event for most people who experience it.
A Word Concerning Visual Hallucinations
As macular degeneration brings about holes in vision, your brain may attempt to “fill in” images that simply aren’t there. While this can be upsetting, it’s actually a testament to how amazing and adaptive our brains really are. This seeing of hallucinations is called Charles Bonnet Syndrome and usually goes away within 18 months or so after losing part of your vision. It’s not a sign of mental illness, but you can certainly speak to a counselor about it if you are unsettled or disturbed by the hallucinatory images.
Macular degeneration can usually be managed and, if you do suffer vision loss, adapted to over time.
Author: John Dreyer Optometrist Bsc(Hons), MCOPTOM, DipCLP
Created: 25 Mar 2017, Last modified: 18 Apr 2019