Styes And Chalazions

What Is It?

A sty, also called hordeolum, is a small abscess of the oil gland associated with an eyelash hair follicle. It typically contains Staphylococcus aureus bacteria, the cause of staph infections. When a sty develops, a small area of the upper or lower eyelid or the corner of the eye becomes red, tender and swollen. Swelling subsides gradually over a period of days after the sty develops an opening, and the pus is able to drain out.

A chalazion, like a sty, is a swelling within the eyelid caused by inflammation of an oil gland. A chalazion differs from a sty in that it does not contain an active bacterial infection. A chalazion is sometimes the aftereffect of a sty. It is less tender but lasts longer.

Natural oils from the eyelid's oil glands must drain through ducts out to the eyelashes. If debris blocks this normal drainage, it may cause a sty or chalazion. Sometimes, this debris accumulates because of a condition called blepharitis, a long-standing inflammation of the edges of the eyelids, with redness, thickening and scales and crusts.

Symptoms

A sty or chalazion begins as a tender red lump or bump within the eyelid at the base of the eyelash. It may cause tearing, light sensitivity and the sensation of having something in the eye. Swelling usually involves only a small area of the lid, but in some cases it can lead to irritation and redness of the whole eyelid. A small, yellowish spot eventually appears in the center of a sty, when the pus collection expands to become visible just beneath the skin or eyelid surface. Pain usually is relieved when the sty ruptures, draining the pus through an opening in the skin, the lid margin or the undersurface of the lid.

A chalazion at first may be red and swollen for a few days, but eventually it changes to a painless, slowly growing, round mass in the lid. The skin around this firm rubbery lump can be moved loosely over the swelling.