Vision loss refers to either complete or partial loss of vision. Depending on the cause, it may occur suddenly or gradually over time, and in one or both eyes. Some types of vision loss are temporary or reversible.
Vision loss is relatively common. According to the Centers for Disease Control and Prevention (CDC), vision problems are among the top 10 disabilities in adults, and one of the most prevalent disabilities in children.
The CDC estimate that 12 million people age 40 or older in the United States have some form of visual impairment, including over 1 million people who are blind.
Experts predict that this number could more than double by 2050 due to the rising rates of diabetes and other chronic diseases in the U.S., along with a rapidly aging population.
There are many possible causes of partial or complete vision loss, including medical conditions, injuries, migraine, and aging.
This article looks at different types of vision loss, the causes of sudden or gradual vision loss, treatments, and coping methods.
Vision loss is the term for losing the ability to see properly. There are different types of vision loss, and these can be caused by different diseases or conditions, including:
- central vision loss, or difficulty seeing things in the center of vision
- peripheral vision loss, or difficulty seeing things out of the corner of the eyes
- general vision loss, when a person may not be able to see anything at all
- night blindness, when a person has trouble seeing in low light
- blurry or hazy vision, when a person’s vision feels out of focus or like looking through a filter
A person may also find themselves unable to see shapes, or only able to see shadows.
Sudden vision loss is vision loss that occurs over a period of a few seconds or minutes to a few days. It can be caused by a variety of conditions.
Around 25–30% of people with migraine have visual aura symptoms. For some, this involves seeing zig-zag lines, sparkles, or spots. For others, it involves tunnel vision, a complete loss of vision, or vision loss to the left or right side.
These visual disturbances are often, but not always, accompanied by a headache. They tend to last less than an hour, and typically persist for 10–30 minutes. Some are gone after a few seconds.
Treatment for migraine may involve painkillers and staying in a darkened room, away from bright lights and loud sounds.
Keratitis can be caused by an infection or injury to the eye. Symptoms include blurred vision, pain, sensitivity to light or vision loss.
This condition is temporary. A doctor will treat it with prescription medication.
Also known as pinkeye, conjunctivitis can cause vision loss. Conjunctivitis is an infection or inflammation of the conjunctiva. It can also cause blurriness, redness, pain, or difficulty seeing.
Conjunctivitis is temporary and usually resolves on its own. For bacterial conjunctivitis, antibiotic eye drops may help.
If a person stares at a screen for too long they may begin to lose vision and perceive things they are looking at are blurry.
This is usually temporary and can be resolved by taking time away from the screen and allowing the eyes to rest.
Practicing the 20-20-20 rule can help prevent eye strain. That means a person looks away from the screen every 20 minutes, at something 20 feet away, for 20 seconds.
Injury to the eye can also cause sudden vision loss. Depending on how serious the injury is, this could be temporary or permanent and treatment may vary accordingly.
People may want to see an eye doctor to assess the severity of the eye injury.
Vision loss is not always sudden. Sometimes it can happen over a long period of time.
Age-related macular degeneration
Age-related macular degeneration (AMD) is an eye disease that can impact a person’s central vision.
AMD is a leading cause of vision loss for people age 50 and older.
This can occur very gradually or quite rapidly. For many people, they begin to see a blurry area near the center of their vision, which may increase in size over time.
Glaucoma is a group of diseases that damage the optic nerve, which is located in the back of a person’s eye.
The symptoms of glaucoma can happen so gradually that a person may not know they have it until they have an eye examination. It can occur in one or both eyes.
Without treatment, glaucoma can eventually cause blindness, beginning with the peripheral vision.
Doctors use a few different types of treatment for glaucoma, including medicines (usually eye drops), laser treatment, and surgery. Treatment cannot reverse damage already caused.
Diabetic retinopathy is a condition causing vision loss and blindness in people with diabetes. It affects blood vessels in the retina, which is the light-sensitive layer of tissue in the back of the eye.
Anyone with any kind of diabetes can get diabetic retinopathy, so it is important that a person with diabetes have regular eye examinations to catch it early.
There are not always noticeable symptoms in the early stages. Treatment may involve medication, laser treatment, or surgery.
In 90% of cases, blindness related to diabetes is preventable. Left untreated, diabetic retinopathy can develop into total and permanent blindness.
Many types of visual impairment are preventable with early diagnosis and quick treatment.
If a person notices that they are losing vision they should book an appointment with their healthcare provider to get it checked out. It could be nothing to worry about, but it is best to get a professional opinion.
If symptoms of vision loss are accompanied by any of the following symptoms, a person should seek immediate medical attention:
- severe headache
- difficulty speaking
- facial drooping
- loss of muscle control on one side of the body
- severe eye pain
These could be signs of a stroke or another serious medical condition.
If a person experiences sudden vision loss, it should be treated as a medical emergency, and they should seek medical attention quickly.
To diagnose vision loss, a doctor may conduct an eye examination. They may shine a light in the person’s eyes or ask them to read the letters on a chart to measure their vision.
Diagnosis may also include a neurological examination to test the function of the eyes and brain.
It can be difficult to cope with vision loss, especially if the loss is permanent. There are some things that a person can do to help themselves cope, and there also are some government services that can help.
A healthcare provider can help direct people to the appropriate resources. People may benefit from both physical and emotional support.
The American Foundation for the Blind provide some resources to help people manage new vision loss.
Ways to cope with partial or total vision loss can include:
- rearranging the home to make it easier to navigate
- applying for Social Security assistance
- talking therapy
- joining a support group
- learning Braille
- using a guide dog
It is not always possible to prevent loss of vision, though people can take steps to look after their eye health.
People can practice good eye health by taking the following steps:
- Resting the eyes. Take a break from staring at a screen every 20 minutes to look at something about 20 feet away for 20 seconds.
- Wearing protective eyewear. Wear safety glasses or goggles when carrying out certain activities, like playing certain sports, doing construction work, or doing home repairs.
- Wearing sunglasses. Choose sunglasses that protect the eyes from 99–100% of both UVA and UVB radiation.
Getting regular eye exams, knowing your risk for eye diseases, eating well, and quitting smoking can also help protect the eyes.
Vision loss can have many causes. Temporary causes include migraine and conjunctivitis. Medical conditions, such as diabetic retinopathy and AMD, can lead to permanent vision loss.
There are often no warning signs or symptoms of eye disease. Early diagnosis and treatment of eye problems are the best ways to keep the eyes healthy, and it is important to seek medical attention if vision loss occurs.