Age-related macular degeneration is an eye disease that can blur the sharp, central vision you need for activities such as driving or reading. “Age-related” means it usually occurs in older people and “macular” means it affects a part of the retina of your eye called the macula.
Age-related macular degeneration (AMD) is the leading cause of irreversible central vision loss for people aged 40 years or older.
Although it doesn’t cause complete blindness, losing your central vision can make it challenging to distinguish between people’s faces, drive, cook food, and fix things around the house.
For some people, AMD progresses gradually. Even if they are early AMD, they may not experience vision loss for a considerably longer time.
While for others, AMD progresses faster and causes central vision loss in one eye or both in a relatively shorter period of time.
Another form of macular degeneration – Stargardt disease or Juvenile macular degeneration – tends to affect children and younger adults.
Types Of Age-related Macular Degeneration
- Dry macular degeneration: Dry macular degeneration accounts for 85 – 90% of AMD cases. It progresses slowly. Although there’s no cure for dry AMD, patients can easily learn the best ways to cope with it.
- Wet macular degeneration: Also called neovascular AMD, it occurs when new blood vessels form under the macula, causing blood and fluid to leak. Wet AMR is more serious as compared with dry AMD and can lead to severe central vision loss. It develops rapidly. If you experience AMD symptoms, go to your eye specialist for immediate treatment.
What Are The Symptoms Of Macular Degeneration?
The symptoms of AMD appear gradually. Most people who have it don’t realize they have it until the advanced stages when vision loss starts to occur.
The primary symptom of AMD is the blurring of the central vision. The outer or peripheral vision remains unaffected. The blurred central vision is still them even when the patient wears glasses.
Dry macular degeneration symptoms:
The symptoms of dry AMD may not occur for about ten years after onset and even longer if the macular degeneration occurs in only one eye. When symptoms do appear, they may include:
- Written or printed texts appear blurry
- Need for brighter light while reading books
- Colours appear less vibrant than they used to
- Cloudy, less defined vision
- Difficulty recognizing people’s faces
- Slow recovery of visual function after being exposed to bright light
Wet macular degeneration symptoms:
All the above-listed symptoms may be present, along with the following:
- A blind spot in central vision that gets bigger when left untreated
- Straight lines appearing faded, broken, or distorted
Wet AMD symptoms progress more quickly than with dry AMD.
Research suggests that early age-related macular degeneration doesn’t always progress to the advanced stages. Taking routine eye exams helps detect early AMD, and adequate measures could be taken on time to keep it from progressing.
What Causes Macular Degeneration?
The exact cause of age-related macular degeneration is not known. But it occurs most commonly in adults and may have something to do with your genetics. This implies if someone in your family has AMD, you can have it too.
Various other factors may also increase your risk for AMD, including obesity, excess body weight, high blood pressure, etc. Read on to find out if you are at significant risk for age-related macular degeneration.
Who Is At A Risk For Age-related Macular Degeneration?
As the name suggests, age-related macular degeneration occurs most often in elderly people.
So, age is considered the primary risk factor for this eye disease. Each decade of life after 40 considerably increases your risk of developing AMD, which is why it is advised to have routine eye exams starting from age 40.
Apart from age, several other factors can increase the risk of developing AMD, including:
- Heredity: Research says that there are specific variants of different genes found in most people with macular degeneration.
- Smoking: Smoking is a critical risk factor for macular degeneration. Research has found that in certain populations, smoking accounts for 25% of age-related macular degeneration, causing severe central vision loss. Another study discovered that people who live with a cigarette smoker are at twice the risk of developing AMD.
- Obesity: Studies show that people with dry macular degeneration who are obese have double the risk of developing advanced AMD than people who have normal body weight.
- High blood pressure: High blood pressure (hypertension) may be associated with the development of AMD.
- Physical inactivity: According to a study, people with dry macular degeneration who performed strenuous activity at least three times a week minimized their odds of developing macular degeneration as compared to those who remained sedentary.
How Is Age-Related Macular Degeneration Diagnosed?
A routine eye exam can help your doctor spot age-related macular degeneration. The eye exam is simple and painless.
Your doctor will use some eye drops to dilate your pupil and check your eyes for AMD and other problems.
If your doctor dilates your pupil, you may experience blurry vision and increased sensitivity to light for a couple of hours after the exam. It’s a good idea to take a friend or a family member with you for the exam as they can help drive you home safely.
This is especially important if you have never had a dilated eye exam before and are unaware of its effects.
After the dilated eye exam, your doctor may order a series of tests, including:
Developed by Marc Amsler, the Amsler grid is a grid of horizontal and vertical lines an eye specialist (ophthalmologist) generally used to monitor the central visual field of a patient. If AMD is present, some of the grid lines may appear to be faded, broken, or distorted.
The test results will give your doctor a better idea of how much damage is caused.
Most people with discernible symptoms find the centre grid lines near the centre of the grid seem faded, broken, or distorted.
The Amsler grid also helps detect the progression of dry AMD to wet AMD at an early, treatable stage.
How Is The Amsler Test Done?
The grid looks like a piece of graph paper, having a small dot at the centre.
With the reading glasses on, hold the grid approximately 13 inches away from the eyes so that you get most of the lines in focus. Cover one eye so that you are testing only one eye at a time.
This is crucial; if you keep both of your eyes open, the good or the healthy eye can compensate for the eye with wet macular degeneration, and you won’t notice any abnormalities in your vision.
An eye without wet macular degeneration often sees all the lines as straight. On the other hand, an eye with wet macular degeneration usually sees some of the lines as curved or blocked by a white, black, or grey region.
This is caused due to the fluid buildup within or under the retina, which could form blisters, making straight horizontal and vertical lines look curved.
Sometimes the fluid disrupts retinal function so much that it causes black, white, red, or grey spots within or near the centre of the visual field.
It is a medical procedure that helps confirm the type of AMD. It is usually conducted when an ophthalmologist suspects wet macular degeneration.
How Is The Fluorescein Angiography Done?
Fluorescein angiography (FA) is generally done at an ophthalmologist’s office, and it takes less than 30 minutes. Here’s what will happen during the procedure:
- Your ophthalmologist will first put eye drops in your eyes to dilate your pupil.
- A yellowish-coloured dye called fluorescein is injected into a vein, generally in your arm. The dye takes nearly 15 – 20 minutes to move throughout your body. Eventually, the dye reaches the blood vessels in your eye, causing them to shine brightly.
- As the dye travels through your retina, a special camera captures several pictures, which help your doctor see any eye problems or decide where to focus treatment.
This test can also cause blurry vision and light sensitivity and so don’t forget to bring your sunglasses to your appointment and have someone drive you home afterwards.
Optical Coherence Tomography
It is an imaging technique that uses low-coherence light to capture micrometre-resolution, two-dimensional and three-dimensional images from within optical scattering media.
How Is The Optical Coherence Tomography Done?
For this procedure, your ophthalmologist may or may not put dilating eye drops in your eyes to widen the pupil and examine your retina.
You will be made to sit in front of the OCT machine and rest your head on a support to keep it still throughout the test.
The device will then scan your eye without touching it. Eye scanning usually takes about 5 – 10 minutes. If your eyes were dilated, you might have blurry vision and sensitivity to light for a few hours after the test.
OCT test results give your doctor more insights into the status of your macula. If the macula has become thinner, thicker, or has transformed in any way, the images will reveal this.
What Treatment Options Are Available For Age-Related Macular Degeneration?
There’s no cure for age-related macular degeneration. Treatment may help delay its progression or keep you from losing too much of your vision. Some available treatment options include:
- Anti-angiogenesis drugs: Certain medications, including aflibercept (Eylea), pegaptanib (Macugen), bevacizumab (Avastin), and ranibizumab (Lucentis), stop the formation of new blood vessels and leakage of blood and fluid from the blood vessels that lead to wet macular degeneration.
Studies suggest that several people who have taken these medications got back their lost vision to some extent. Your doctor may recommend taking this treatment multiple times for optimum results.
- Laser therapy: Laser therapy helps destroy abnormal blood vessels growing in your eye and treats macular degeneration.
- Photodynamic laser therapy: For this therapy, your doctor will inject a light-sensitive drug called verteporfin (Visudyne) into your bloodstream, which is then absorbed by the abnormal blood vessels. Then, your doctor will shine a laser into your eye to stimulate the medication to destroy those blood vessels.
- Low vision aids: These devices have special lenses or electronic systems to produce larger images of nearby things. They help people with macular degeneration to make the most of their remaining vision.
Researchers are studying recent treatments for macular degeneration, but they are still experimental. These include:
- Submacular surgery: This procedure helps remove abnormal blood vessels or blood.
- Retinal translocation: This is a surgical procedure your doctor carries out to destroy abnormal blood vessels under the centre of your macula, where a laser beam can’t be used safely. Your doctor will move the centre of the macula away from the abnormal blood vessels to a healthy region of your retina. This prevents the formation of scar tissue and further damage to your retina.
Then, the doctor will use a laser to destroy abnormal blood vessels. This is a promising treatment that offers patients a chance to improve their central vision potentially to the extent that may make reading books and drive feasible.
Age-related macular degeneration can lead to several complications, including:
- Adapting to vision loss: Vision loss can be really difficult to accept, especially when the simplest of tasks like reading becomes challenging. This may foster feelings of anxiety, stress, and depression. Talking to a healthcare professional might be helpful for people to find new ways to cope with it.
- Visual hallucinations: If there’s severe vision loss, it can greatly affect some people. This may be because the brain generally compensates for the visual data it is not receiving by producing fantasy images, usually from the stored memory.
People are generally terrified to talk about visual hallucinations because they fear that it may indicate a mental issue.
Please note that these hallucinations only indicate visual problems and not a mental health concern.
- Driving: AMD can affect a person’s ability to drive. Ask your doctor if your vision changes will impact your ability to drive.
- Cardiovascular risk: AMD shares some risk factors with cardiovascular diseases, and studies suggest that people with AMD are highly susceptible to developing symptoms of cardiovascular disease.
How To Minimize Your Risk For AMD?
Following are some of the best tips to prevent age-related macular degeneration:
- Quit smoking: Smoking cessation is the number 1 tip for AMD prevention. Smoking may double your risk of developing AMD. It exposes you to dangerous free radicals and unstable molecules that can lead to cellular damage and keep the nutrients from reaching the retina of your eye. The sooner you can quit smoking, the better.
- Eat leafy greens: Fill your plate with kale, spinach, etc., among other leafy greens. They are loaded with antioxidant vitamins, which will offer protection against cellular damage from free radicals, which in turn will help keep macular degeneration at bay.
- Know your family history: People having any immediate relatives affected by macular degeneration have a significantly greater risk of developing it too. Those with a family history of AMD need to be extra vigilant for potential symptoms such as seeing straight lines appear to be faded, broken, or distorted, difficulty recognizing people’s faces, difficulty adapting to low light, etc.
- Wear sunglasses: Sunglasses offer protection against blue light and UV light that can cause retinal damage from constant exposure. Lifetime use of sunglasses can be helpful to prevent macular degeneration.
- Take supplements: People with nutrient deficiencies can consider multivitamins. This isn’t a treatment or a cure for AMD but can reduce your risk of developing more severe forms of the condition.
- Maintain healthy blood pressure and body weight: Poor blood flow due to high blood pressure (hypertension) can restrict blood flow to the eyes as well, contributing to AMD. Losing excess weight is a proven way to lower blood pressure levels; even shedding a few pounds can help, especially when you have hypertension. There is a direct link between changes in both systemic blood pressures and intraocular pressure, says NCBI. So, people with hypertension may also develop the risk of ocular hypertension.
- Test your vision regularly with an Amsler Grid: Amsler Grid that helps doctors to identify vision problems due to macular degeneration can be used at home also. If the straight horizontal and vertical lines appear wavy or distorted or you notice any other changes in your vision, call your doctor immediately. Keep your Amsler grid at a place that reminds you to check your central vision daily.