Sty vs. Chalazion
A sty is sometimes confused with a chalazion (see below), which is a cyst or a specific type of scarring due to chronic inflammation arising in the meibomian glands of the eyelid. A chalazion may develop when the infection of a sty persists over time, resulting in scarring around the meibomian gland. In contrast to a sty, a chalazion is usually painless.
Quick GuideCommon Eye Problems and Infections
- A chalazion is a lump in the upper or lower eyelid caused by obstruction and inflammation of an oil gland of the eyelid.
- A chalazion is not a tumor or growth and does not cause permanent changes in the vision.
- A chalazion is very common and usually goes away without the necessity of surgery.
What is a chalazion?
A chalazion is a lump in the upper or lower eyelid caused by inflammation of a gland of the lid. It may be soft and fluid-filled or firmer. A chalazion is also referred to as a meibomian cyst, tarsal cyst, or conjunctival granuloma.
What are these eyelid glands?
Eyelid glands are called the meibomian glands. They are also known as the palpebral glands, tarsal glands, or tarsoconjunctival glands. There are 30-40 of these glands in each of the upper and lower lids. These glands produce a thick liquid secretion that is discharged into the tear film of the eye. This liquid is a mixture of oil and mucus and is called sebum. The liquid acts to maintain lubrication of the surface of the eye. The tiny openings of each of these oil or sebaceous glands are just behind the eyelashes at the lid margins of both the upper and lower eyelids.
What causes a chalazion?
The narrow opening through which a meibomian gland secretes its material can become clogged from narrowing of the opening or hardening of the sebaceous liquid near the opening. If this occurs, the gland will have a backup of the material it secretes and the obstructed gland will swell. This leads to thickening of the walls of the gland and leakage of oil into the lid itself, causing inflammation both within the gland and the eyelid. This inflamed enlargement is a chalazion.
Medically Reviewed by a Doctor on 5/4/2016