Chalazion
A chalazion is an enlargement of a deeper oil gland in the eyelid that results from an obstruction of the gland opening at the edge of the eyelid.
At first, a chalazion looks and feels like a stye: swollen eyelid, mild pain, and irritation. However, these symptoms disappear after a few days, leaving a round, painless swelling in the eyelid that grows slowly for the first week. Occasionally, the swelling continues to grow and may press on the eyeball and cause vision changes. A red or gray area may develop on the underside of the eyelid.
Most chalazions disappear without treatment after 1 to 3 months. If hot compresses are applied several times a day, chalazions may disappear sooner. If they remain after 2 weeks or longer or if they cause vision changes, a doctor can drain them or inject a corticosteroid.
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