The eye condition known as a chalazion is caused by a blockage of a duct on the eyelid, creating a small bump on the lid. It is also known as a Meibomian gland lipogranuloma. The duct can be blocked by solidified oil or, in rare cases, by a tumor. Chalazions are usually harmless. Some disappear without medical treatment, but large chalazions or cancerous chalazions may require surgery.
The duct on the eyelid that is affected by a chalazion is known as a Meibomian gland. These glands produce oil that is a component of tears. Each eye has about 100 Meibomian glands, which are located on both the upper and lower eyelid, close to the eyelash line.
Meibomian glands have ducts that drain away the oil from the eyelid. Sometimes, these ducts are blocked by hardened oil or a skin tumor, and a chalazion results. This is not an infection but merely a blockage.
A doctor diagnoses the condition through a visual examination of the eyelid. Chalazions appear red and swollen. They may also be painful or feel warm due to the inflammation. Other symptoms include an aversion to light and more tear production than usual.
A chalazion is different from a sty. A sty is an infection of the gland and usually hurts more than a chalazion. Chalazions may heal themselves over a few weeks.
Warm compresses placed on the eye several times a day can help to soften the oil and resolve the blockage. Antibiotic eye drops do not help cure the condition. Medical treatment is not usually necessary unless the chalazion gets larger, has been present for more than one month, or if a patch of eyelashes falls out.
Sometimes chalazions increase in size, and surgical treatment is required. The surgeon makes the incision from underneath the eyelid to prevent scarring. A large chalazion may cause vision problems as it presses on the cornea, but these problems go away if the chalazion is removed. Alternatively, a doctor may prescribe steroid injections. On rare occasions, the blockage is caused by a tumor of the skin, and in suspected cancer cases, a doctor will perform a biopsy.
The only preventative measure for the condition is thorough cleaning of the eyelid. People who regularly suffer from the condition can use baby shampoo on the eyelash area. Keeping the oil level down reduces the chance of excess oil blocking the duct.