A chalazion is a swollen, pain-free lump on the eyelid. It gradually forms when the meibomian gland, a sebaceous (oil) gland, is blocked. A chalazion is sometimes called an eyelid cyst or a ...

The primary causes of a chalazion are obstruction of the oil glands (meibomian glands ... Blepharitis does not cause a lump on the eyelid. However, blepharitis can increase your risk of getting ...

Medically reviewed by Johnstone M. Kim, MD Swollen eyelids, top or bottom, can have many causes, including allergies, infections, and blocked oil glands. While most aren't serious, eyelids can also ...