If This Happens When You're Reading, Call Your Doctor Right Away
One specific symptom could be a sign of a serious eye disease—and can even lead to blindness.
Our eyes allow us access to a lot of valuable information—and it's not just about what we see, but what our vision can tell us about our health. While the eyes take in an amazing amount of data—think seven million cone cells in your retina detecting five hundred shades of just a single color—they also send us warning signs about myriad conditions ranging from our brain health to thyroid issues.
One particular change in vision can signal a disease called geographic atrophy (GA). "GA is an advanced form of dry age-related macular degeneration (AMD), in which the cells critical to central vision—such as reading or driving vision—atrophy, or 'die-off,' due to this complex inherited disease," explains Nancy Holekamp, MD, an ophthalmologist at the Pepose Vision Institute in Missouri.
Since 42 percent of patients with GA are legally blind due to the condition, it's important to know the symptoms, so you can speak to your doctor right away. Read on to find out about one particular symptom you might notice when you're reading.
Macular degeneration is a common cause of vision troubles.
Among people age 50 and older, age-related macular degeneration is the most common cause of severe loss of eyesight. The macula is located at the back of the eye. "It is only about 5mm across, but is responsible for our central vision, most of our color vision, and the fine detail of what we see," according to the Macular Society. "The macula has a very high concentration of photoreceptor cells—the cells that detect light." These cells then send signals to the brain.
Macular degeneration interferes with this process, and comes in two forms: dry and wet, reports The New York Times. "The dry form is milder and usually has no symptoms, but it can degenerate into the wet form, which is characterized by the growth of abnormal blood vessels in the back of the eye, potentially causing blurriness or vision loss in the center of the field of vision," they write. This can affect our vision in numerous ways, and cause a specific problem when reading.
People with one type of macular degeneration may notice something strange when reading.
When GA occurs and parts of the retina atrophy, your vision may change. Dim or blind spots can occur, resulting in difficulty seeing (especially in low light), dulled vision, or colors that appear washed out and less vivid. An early symptom of GA occurs when reading. It may appear as though numbers, letters, or "one or several words are 'missing,'" according to the Bright Focus Foundation. This happens because of the cells that have atrophied, which result in "missing spots" in vision. Patients can also have difficulty seeing (especially in low light), dulled vision, or perceive colors as washed out and less vivid.
"Patients with GA slowly but progressively lose the fine vision needed for reading, driving, and seeing people's faces," says Holekamp. "They have missing spots in their central vision, causing an inability to see detail, but they still retain peripheral vision throughout the course of the disease." In addition, "people with GA gradually but progressively develop difficulty reading," Holekamp explains. "Ultimately, many affected individuals require more light, large print, black letters on a white page, and perhaps a hand-held magnifier."
There's no known cause of geographic atrophy, but there are risk factors.
Approximately one million Americans are affected by GA. "Age related macular degeneration (AMD) is a leading cause of visual impairment and severe vision loss," according to an article in the Journal of the American Heart Association. "It accounts for 8.7 percent of all blindness worldwide and is the most common cause of blindness in developed countries, particularly in people aged [over] 60 years."
There is no known cause, but "advancing age and a family history of age-related macular degeneration are the two main risk factors for developing GA," says Holekamp, adding that the American Academy of Ophthalmology recommends that people over the age of 50 have yearly eye exams.
"Only an eye doctor can diagnose GA, and the diagnosis of age-related macular degeneration can be made during that annual examination," she says. "Be sure to tell your eye doctor if you have a family history of age-related macular degeneration, as this disease tends to run in families."
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Protecting your eyes is important for overall wellness.
According to Prevent Blindness, certain additional factors that can increase your risk for GA include hypertension, high cholesterol, obesity, and diabetes. Heart disease can also be linked to eye health, as well as lifestyle choices such as tobacco use and maintaining a healthy diet.
Being proactive about your eye health is important not just to help prevent GA, but other conditions including ulcers, vision impairment, and cancer. Taking breaks from screen time, practicing healthy contact lens habits, and protecting your eyes from the sun are all ways you can take care of your eyes and lower your risk factors for diseases and other issues.
There are also management options for those living with GA. "In addition to regular eye examinations, the disease can also be managed through visual rehabilitation with the use of magnifiers and low vision aids 2," advises Eye See You.
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