Stye is the common term used for an acute infection of the oil glands which lubricate the eyelashes. They are located on the eyelid margins. The correct medical term is hordeolum. Sties are usually caused by the Staphylococcus germ and are very common in children and in patients with chronic eye lid infections.
Sties tend to be painful, especially in the early stages when swelling and redness. Treatment consists of frequent hot packs, and in some cases antibiotic ointment may be helpful. Rarely is surgical drainage necessary.
A chalazion is a larger nodule of inflammation that occurs in the larger Meibomian oil glands of the eyelids. These are treated in a similar manner, but sometimes require surgery, when they are large or if they persist for several months.