What Are Chalazia and Styes?
A chalazion and a stye are both lumps in or along the edge of an eyelid. In some situations it may be difficult to distinguish between a chalazion and stye.
A stye is a red, sore lump near
the edge of the eyelid.
A stye often appears as a red, sore lump near the edge of the eyelid, caused by an infected eyelash follicle. When a stye occurs inside or under the eyelid, it is called an internal hordeolum (pronounced "hor-dee-OH-lum").
The term chalazion (pronounced kuh-LAY-zee-un) comes from a Greek word meaning "small lump." A chalazion forms when an oil-producing gland in the eyelid called the meibomian gland becomes enlarged and the gland opening becomes clogged with oil.
A chalazion is an enlargement of
an oil-producing gland in the
Chalazia tend to develop farther from the edge of the eyelid than styes. Often larger than stye, a chalazia usually isn't painful. It is not caused by an infection from bacteria, and it is not a cancer. Sometimes, when a a stye doesn't heal, it can turn into a chalazion.