Top Causes of Blindness
Could you be at risk for blindness? More than 1 million people in the U.S. over 40 are blind, while millions of people of all ages suffer from vision impairments, according to the Centers for Disease Control and Prevention (CDC). Although injuries can cause blindness, several eye diseases are responsible for most cases of vision loss in the U.S.
What Are Visual Impairments
Visual impairments interfere with your ability to see clearly. Low vision occurs when your eyesight is 20/70 or worse and can't be improved by wearing eyeglasses or contact lenses. Legal blindness is defined as vision that's 20/200 or worse, even with glasses or contacts. Total blindness is the inability to see anything.
What Causes Blindness?
Although eye injuries can cause blindness, most cases are caused by eye diseases. The diseases most likely to cause blindness or vision loss in the U.S. include age-related macular degeneration (AMD), diabetic retinopathy, glaucoma, and cataracts, according to the CDC.
Age-Related Macular Degeneration (AMD)
AMD causes blurriness or a blind spot in the center of your vision. The disease affects 11 million people and is the leading cause of blindness in people 60 and older in the U.S., according to Bright Focus Foundation.
The dry form, the most common type of AMD, happens when cells in the macula begin to break down. The macula is the central part of the retina, the light-sensing tissue at the back of the eye. There is currently no treatment for the dry type of AMD. Wet AMD happens when abnormal blood vessels grow in the macula and leak fluid and blood. Several treatments are available to stop leaks and prevent new blood vessels from growing.
As diabetes cases increase in the U.S., more people are at risk of developing diabetic retinopathy, a serious eye disease that can lead to blindness. The disease damages blood vessels in the retina, causing them to leak. Leaky blood vessels may trigger swelling in the macula and the growth of abnormal blood vessels that also begin to leak.
Diabetic retinopathy can cause permanent vision loss or blindness without prompt treatment. Treatments that reduce swelling and seal leaking blood vessels can protect your vision and limit vision loss.
Glaucoma damages the optic nerve, the connection between the brain and the eyes. Unfortunately, the damage causes irreversible vision loss. Open-angle glaucoma slowly damages the optic nerve and usually affects peripheral (side) vision first. This type of glaucoma usually doesn't cause any noticeable symptoms at first.
Angle-closure glaucoma happens quickly and causes blurred vision, eye pain, headache, and nausea and vomiting. Medication decreases pressure in open-angle glaucoma, while laser treatment or surgery treat fluid blockages that cause high pressure in angle-closure glaucoma.
More than 24 million people over 40 have cataracts, according to the National Eye Institute. Cataracts happen when the clear lens inside the eye becomes cloudy. The lens helps focus light rays on the retina where they're turned into electrical signals that are sent to the brain.
Cataracts block light rays from reaching the retina and cause a variety of symptoms, including blurry vision, halos around lights, glare and trouble seeing well in low light. If the cataracts aren't removed, you may eventually become blind. Fortunately, replacing the cloudy lens with an intraocular lens implant during cataract surgery will help you avoid blindness.
What You Can Do to Prevent Blindness
Reducing your risk of blindness starts with:
- Wearing Sunglasses. Exposure to ultraviolet A (UVA) and ultraviolet B (UVB) rays may increase your risk of cataracts, age-related macular degeneration, according to All About Vision. Choose sunglasses that offer protect form both types of ultraviolet light, and wear them year-round.
- Putting on Goggles. Whether you're playing sports, sawing wood, or working with chemicals, goggles protect your eyes from serious injuries that can lead to blindness or vision loss.
- Scheduling Annual Vision Exams with Your Ophthalmologist. Eye diseases may not cause changes in vision at first, yet can still damage your eyesight. Your eye doctor can spot subtle changes during your annual vision exam and offer treatments that help you avoid vision loss. Don't wait for you annual exam if you notice a change in your vision. Call the eye doctor immediately.
Is it time for your vision exam? Give us a call to schedule your appointment.
National Eye Institute: Eye Health Statistics
Centers for Disease Control and Prevention: Fast Facts of Common Eye Disorders, 6/9/2020
Bright Focus Foundation: Age-Related Macular Degeneration: Facts and Figures, 10/18/2022
All About Vision: 5 Eye Conditions Linked to Sun Damage, 6/22/2022
Centers for Disease Control and Prevention: Common Eye Disorders and Diseases, 6/3/2020