A hordeolum or a chalazion is commonly called a stye. It is caused by an infection of the sebaceous glands of the eyelid. These glands are small and reside at the base of the hair follicles. These glands secrete a very clear oil that makes up an important part of the normal tear fluid.
Hordeolum cause mild to moderate pain or tenderness especially when the area is touched. Initial treatment may include special cleansing of the eyelid area, digital massage, hot compresses, and topical, and/or oral antibiotics. In some cases, the gland may form a granuloma or scar tissue and form a small, painless lump in the eyelid called a chalazion. Although harmless the chalazion may be removed surgically if symptoms persist despite palliative treatment or if there are cosmetic concerns.