Summary

• Stye (hordeolum) is an acute infectious process involving abscess formation at the upper or lower eyelid.
• The most commonly involved bacterial pathogen is Staphylococcus aureus.
• Chalazion is an inflammatory condition caused by a foreign body reaction to sebum released by meibomian glands.
• Styes are typically tender to palpation, while chalazia are not.
• Dacryoadenitis and dacryocystitis can be confused with stye; their respective locations (lateral upper lid and inferior to the medial epicanthus) are key.
• Most styes and chalazia resolve with warm compresses and topical antibiotics.
• Recurrent lesions may require biopsy to exclude carcinomas. Recurrent chalazia may require excision.