Entropion is a medical condition in which the eyelid folds inward. It usually occurs in the lower eyelid, but it can affect either. The reverse is a condition called ectropion, in which the eyelid turns outward.
A person with entropion will notice that their eyelashes and skin are rubbing against the cornea of the eye. This causes the eye to water, as well as inflammation, discomfort, irritation, or pain.
The eyelid may turn inward permanently, or it may only happen when the person shuts their eyes tightly or blinks hard.
Entropion typically has a genetic cause. In some, rare cases, the lower eyelid has an extra fold of skin.
If the condition affects both eyes, this is called bilateral entropion.
Entropion is very rare in children and young adults, but it may affect up to 2.1 percent of people over the age of 60 years, according to the American Academy of Ophthalmology.
Signs and symptoms of entropion can include:
- irritation and a feeling that something is stuck in the eye
- excessive watering of the eyes, which is called epiphora
- crusting, or mucous discharge, on the eyelid
- pain in the eye
- sensitivity to light, which is called photophobia
- sensitivity of the eye to wind
- sagging skin around the eye
- redness in the whites of the eyes
Vision problems can also occur, especially if there is damage to the cornea.
Aging can lead to entropion. As a person gets older, there is more loose skin around the eyelids, the muscles under the eyes weaken, and the tendons and ligaments in the area relax.
Scarring of the skin can be a contributing factor. Scarring may result from trauma, surgery, radiation to the face, or chemical burns. It can alter the natural curvature of the eyelid.
Also, a bacterial infection, such as trachoma, can cause the inner surface of the eyelids to become rough and scarred. The infection is uncommon in developed nations, but it affects tens of millions of people globally.
In addition, eye surgery can lead to eyelid spasms, which can cause the eyelid to fold inward.
Congenital issues can, rarely, cause entropion that is present from birth.
A physician can usually diagnose entropion with a routine examination of the eye. They may also pull on the eyelid and ask the person to close their eyes tightly or blink hard. Special diagnostic tests do not tend to be necessary.
If the condition could have resulted from scar tissue or surgical intervention, the doctor will also check the surrounding tissue and the inside of the eyelids.
Identifying the cause of entropion will help a doctor determine the most effective treatment.