Age-related macular degeneration (AMD) is a condition of the retina of the eye. It occurs due to damage caused to macula – a part of retina responsible for detailed and sharp vision, i.e., visual acuity. A person with AMD loses central vision. It becomes a challenge to notice fine details, irrespective of the distance at which the object is being observed. However, the peripheral vision does not get affected. For example, you can consider a person looking at a clock. He may be able to notice the numbers on the clock, but not the hands.
AMD is a quite a common eye condition. In people above the age of 50, AMD is the leading cause of vision loss.
In some people, AMD progresses so slowly that loss of vision may not occur for a considerable duration. However, in some cases, it may advance really fast and may lead to vision loss either in one or both the eyes. As AMD advances, there may be appearance of blurred area near the center of vision. With the passage of time, the area that appears blurred may grow larger or there may be blank spots in the central vision. AMD can interrupt with simple everyday activities like not being able to recognize faces, inability to drive, and do household chores like cooking or sewing.
Macula is composed of many cells that sense light and provide a sharp and clear image. It is present at the back of the eye and is thought to be most sensitive part of the retina. Retina converts light to electrical signals and sends across these signals to the brain via the optic nerve. It is here, where the signals get transformed into the images that we see. When macula gets damaged, the view becomes distorted and dark. Macular degeneration is bilateral, i.e., it occurs in both the eyes but not at the same pace.
Around 11 million Americans have some form of age-related macular degeneration. The figures are expected to double by the year 2050. The number of people having macular degeneration will be around 196 million by 2020 and is expected to rise up to 288 million by the year 2040, worldwide. It is a leading cause of vision loss in people above the age of 50. It causes irreversible blindness and visual impairment.
The chances of getting age-related macular degeneration increase from 2% in the age of 50-59 to 30% in those, who are above 75.
According to a study conducted by the researchers from University of Wisconsin School of Medical Sciences, around 6.5% of Americans older than 40 have macular degeneration to some extent. AMD is fairly common among older White population, affecting more than 14% Americans in the age group of 80 and above. Among Americans, who are above the age of 50, advanced AMD affects 2.1% of the people. It has been seen that it affects Whites more than Blacks and other ethnic groups.
There are two types of AMD:
Factors that may increase the risk for AMD are:
The symptoms of Stargardt disease (an inherited retinal disease) and age-related macular degeneration are almost similar. Stargardt disease is also a type of macular degeneration. Stargardt is, however, diagnosed in children and teenagers. It usually occurs in the age of 6-20 years. This happens as kids notice difficulty in reading or working in bright lights. The cause and treatment of Stargardt disease is different from age-related macular degeneration.
Thus, in order to correctly diagnose the condition, one must consult a doctor or a health care provider, so that appropriate treatment methods may be adopted.
The exact cause of AMD is not yet known. However, as the name suggests, this condition develops with aging. When the doctors first started studying this condition, they thought that drusen showed some type of infection or inflammation of the choroid – a vascular layer of the eye, lying between the sclera and retina. Environmental factors are also at play. Exposure to light, use of certain drugs and ingestion of toxins and deficiency of various nutrients are other factors that can lead to the development of AMD.
Another cause of AMD is abnormalities in specific genes. It has been observed that some types of macular degeneration are hereditary. This is important to understand macular degeneration. When AMD is caused by a dominant gene, different family members may get affected. These families can be studied by modern molecular genetic methods in a way, so that the underlying cause may be identified.
Causes of AMD are complex, both hereditary and environmental. Researchers and scientists are studying to understand what causes the macula to degenerate. The greatest risk factor is age. People over 60 have a greater chance of developing the condition. People in their middle ages have 2% risk of getting AMD. People above 75 are at 30% risk of developing the condition.
The healthy habits as discussed below can help in protecting your vision and improving overall health:
When you go for an eye exam, your doctor may want you to look at an Amsler grid. This will point out any blurry or dark spot in the field of view of the patient. The eye specialist will look inside the eyes through a particular lens made for this purpose. Through this lens, doctor will examine if there are any changes in the macula and retina.
Further, the doctor will put eye drops in the eyes to expand the pupil. This will make it easy for him to look at the inside of the eye.
Fluorescein angiography may also be done to see what’s happening with the retina. In Fluorescein angiography, a yellow dye is given into the arm vein. The dye gets transported through the blood vessels. Photos are taken by a specialized camera as the dye travels through the blood vessels. This further shows if there is growth of abnormal blood vessels in the retina.
Optical Coherence Tomography (OCT) is another way of looking closely at the retina. Retina is scanned by a machine and very fine images of retina and macula are created.
Going for timely treatment, one can slow down the degeneration of the macula and prevent severe vision loss. Some treatment options are discussed below:
There are some treatment methods under experimentation. These are discussed below:
As such, there are no over-the-counter (OTC) medications available for AMD. Mostly drugs and eye drops are available by prescription only. For managing AMD by self, have regular eye exams and find out if you are at a higher risk for having eye diseases.
If you find changes in vision, see a doctor immediately. Some signs to look out for are hazy vision, double vision and not being able to see in low light conditions. Regular exercise or even walking can reduce the risk of age-related macular degeneration.
If you are traveling outside, do not forget to wear sunglasses that will shield your eyes from the harmful UV rays. Eat a lot of fruits and green vegetables as these have antioxidants and essential nutrients that keep your eyes healthy.
The following are natural ways to cure AMD:
Practicing a healthy lifestyle may decrease the risk of getting AMD. Do not smoke as it is bad for the eyesight. Exercise often as it reduces inflammation, which may cause AMD. Also, eat a nutritious diet rich in vitamins and minerals that are good for your eyes.
Academician, Shelly's rich experience as an academic and research professional speaks volume. Her fields of interest are genetics, biotechnology and drug research. Shelly keeps herself abreast with latest scientific researches all around the globe and loves to write about the same.
Our lives have been dealing with some disastrous happenings due to the global health crisis.…
A study led by researchers at the University of California San Diego School of Medicine…
Researchers from several research institutes presented their results at the American Geophysical Union's fall meeting.…
A lot of us wait for the winters to arrive as it brings relief from…
While the world is aiming to develop vaccines to control covid-19, researchers at the Institute…
Also known as hypertension, high blood pressure affects large population across the world. Hypertension is…