What is a Chalazion?

A Chalazion is a small bump in the eyelid that develops when a tiny oil gland becomes blocked. The eyelid has approximately 100 of these oil glands, which are located near the eyelashes. They secrete oil into the tears to lubricate the eye. When one of these glands becomes blocked, it will cause a visible lump in either the upper or lower eyelid. This lump may increase in size over days to weeks.

A Chalazion is not a sty. A Chalazion is an inflammation of the area around the affected oil gland, while a sty is a bacterial infection of an oil gland. Stys tend to be painful and generally look infected, while Chalazions are generally not painful but produce swelling and warmth, and are usually larger than a sty.

What causes a Chalazion?

A Chalazion is caused by the oil in the gland becoming too thick to flow out of the gland. Without anywhere to go, the oil builds up inside the gland and forms a lump in the eyelid. The gland wall may break, releasing the oil into the tissue of the eyelid, causing inflammation and sometimes scar tissue.

Symptoms of a Chalazion

  • A visible lump on either the upper or lower eyelid
  • Eyelid tenderness
  • Increased tearing
  • Redness and swelling on the eyelid
  • Sensitivity to light

How are Chalazions treated?

Chalazions may be annoying, but they are rarely serious. An exam of the eyelid confirms the diagnosis. The primary treatment is to soften the hardened oil blocking the duct, and begin to promote drainage and healing. If the Chalazion continues to get bigger, it may need to be removed with surgery. This is usually done from underneath the eyelid to avoid a scar on the skin. Most Chalazions will disappear in about a month.

You should contact your ophthalmologist if the swelling gets worse and continues for longer than 1 month. A large Chalazion can interfere with vision and cause astigmatism due to pressure on the cornea.