What distinguishes an internal stye from an external one?

An internal stye, also known as a meibomian gland obstruction, presents itself differently from an external stye, which is typically associated with hair follicles of the eyelashes. The defining characteristic of an internal stye is that it often results in a painful localized swelling on the inside of the eyelid, which can be quite uncomfortable for the patient. This inflammation and swelling are due to the blockage and subsequent infection of one of the meibomian glands, leading to the buildup of oils and bacteria.

This distinction in symptoms is crucial for diagnosis and treatment. The pain associated with internal styes is generally more significant because of the pressure exerted on sensitive structures within the eyelid. Additionally, understanding the location of these swellings helps healthcare providers determine the appropriate management and differentiate it from external styes, which typically manifest as bumps on the outer portion of the eyelid.