Chalazion and Stye
A chalazion is a mass or cyst in the upper or lower eyelid that is benign, or non-cancerous. Chalazions are often chronic, which means that they recur frequently.
A chalazion starts with inflammation of the meibomian gland. This is one of the glands of the eye that produces a substance to keep the eyelids separated. The eyelids may stick together, and one of the tear ducts becomes blocked. The eyelid then becomes inflamed and a cyst, or chalazion, develops. This condition may take a few days to a few weeks to develop.
If the chalazion is left untreated, the eyelid can be permanently scarred, resulting in lost or crooked eyelashes. A large, untreated chalazion can cause astigmatism, and blurred vision.