As our population ages, vision loss from eye diseases is increasing.
According to the National Eye Institute (NEI):
About 3.3 million Americans aged 40 or older are blind or have low vision. This is about 1 in every 28 people.
By 2020, that number could be 5.5 million -- a 60% increase.
NEI has identified the most common eye diseases in people over age 40 as:
Age-related macular degeneration
Diabetic eye disease
To catch eye conditions early and help...
Most people develop a minor eyelid twitch at some point in their lives. Although the cause is generally unknown, it may be associated with:
This minor form of twitch is painless and harmless. It usually goes away on its own. But it can be quite annoying. And that's especially true if the spasms are strong enough to cause the eyelids to completely shut and then reopen.
In some cases eye twitching is more than a temporary nuisance. Some people have spasms that occur frequently throughout the day. Symptoms can recur for days, weeks, or even months. That can cause a lot of emotional distress. It can interfere with quality of life.
In its most serious forms, which are relatively uncommon, eye twitching can become chronic. It can cause persistent winking and squinting. If it progresses to the point where you have difficulty keeping your eyes open, it can cause severe vision impairment.
Sometimes, eye twitching can be a sign of eye conditions such as:
Blepharitis (inflammation of the eyelids)
Very rarely, it can be a sign of a brain or nerve disorder, such as:
Eye twitching can also be a side effect of certain medications. The most common offenders include drugs used in the treatment of psychosis and epilepsy.
Types of Eye Twitching
There are three common types of eye twitch:
Minor eyelid twitch
Benign essential blepharospasm
Minor eyelid twitch is often associated with lifestyle factors, such as:
Lack of sleep
Use of alcohol, tobacco, or caffeine
Minor eyelid twitch also can be caused by irritation of the surface of the eye (cornea) or the membranes lining the eyelids (conjunctiva).
Sometimes the cause of minor eyelid twitch cannot be identified. In almost all cases it is painless and harmless.
Benign essential blepharospasm usually develops in mid- to late-adulthood and gradually worsens. It affects about 20,000 to 50,000 Americans. It's twice as common in women as in men. It is not a serious condition but can interfere with your daily life in more severe cases.
Typically, benign essential blepharospasm starts with excessive blinking and/or eye irritation that may be triggered by:
Irritants such as bright light, wind, or air pollution
As the condition worsens, it may lead to an increased sensitivity to light, blurry vision, and facial spasms. In severe cases, the spasms can become so intense that the eyelids stay shut for up to several hours.
Researchers believe that benign essential blepharospasm may result from a combination of environmental and genetic factors. Although the condition is usually random, it sometimes runs in families.
Hemifacial spasm is quite rare and involves more than just the eyelid muscles. It also usually involves the muscles around the mouth. Unlike other types of eyelid twitching, it usually affects only one side of the face.
In most cases, hemifacial spasm is caused by an artery pressing on the nerve to the facial muscles.