Stye is a term used often by the general public to denote a small localized swelling/inflammation of the eyelid. Symptoms of eye infection may include redness, itching, swelling, discharge, pain, or problems with vision. Treatment depends on the cause of the infection and may include compresses, eye drops, creams, or antibiotics.

A hordeolum (or a stye) is term used by the medical profession to denote a localized inflammation and/or infection of the hair follicles of the eyelid or the meibomian glands. It is usually an acute problem but can be recurrent. Generalized cellulitis can also occur. In 90-95% of cases, Staphylococcus aureus is the cause.

External hordeolum – a hordeolum of hair follicles that usually has its leading edge pointing externally to the eyelid. It affects the sebaceous glands of Zeis or the apocrine sweat glands of Moll which both service the hair follicles. There is often purulent material on the eyelashes and lid margin.

Internal hordeolum – a hordeolum of the meibomian glands lying within the tarsal plates that usually has its leading edge point internally to the eyelids.

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