Chalazion
A chalazion [kuh-lay-zee-uhn] is a benign eyelid cyst that is either skin-coloured and hard to the touch, or red and swollen. They are often mistaken for styes. Chalazions are meibomian cysts; the meibomian glands make the lipid in your tears that lubricates the eye and prevents dry eye/evaporation. These oil glands can get blocked, which causes an inflammation – a chalazion. Sometimes, chalazions can go away by being treated with the application of a warm compress to the affected eyelid (but no squeezing); but if they are causing distress or are proving stubborn, chalazions can be surgically drained under local anaesthetic in a simple procedure; the surgical incision being made on the inside of the eyelid (to hide any scar).