A chalazion is caused by a blockage in one of the meibomian glands of the eyelid. These glands produce an oily substance that helps lubricate the eye.
Understanding the Meibomian Glands
The meibomian glands are located within the eyelids, just behind the eyelashes. Their primary function is to secrete meibum, an oily fluid that forms part of the tear film. This tear film coats the surface of the eye, keeping it moist and comfortable.
The Blockage Explained
When the duct of a meibomian gland becomes blocked, the oily secretions cannot escape. This buildup of oil leads to inflammation and the formation of a small, painless bump in the eyelid – a chalazion.
Factors Contributing to Blockage
While the exact cause of a blockage isn't always known, several factors can increase the likelihood of developing a chalazion:
- Meibomian gland dysfunction (MGD): This is a chronic condition where the meibomian glands don't function properly, leading to thickened or insufficient oil secretion.
- Blepharitis: Inflammation of the eyelids, often caused by bacteria or skin conditions like seborrheic dermatitis.
- Rosacea: A skin condition that can affect the eyes, causing blepharitis and MGD.
- Poor eyelid hygiene: Infrequent or improper cleaning of the eyelids can contribute to blockage.
- Hormonal changes: Hormonal fluctuations can affect oil production and contribute to blockages.
In Summary
A chalazion results from a blocked meibomian gland preventing the normal release of oily secretions, leading to inflammation and a bump in the eyelid. Contributing factors include meibomian gland dysfunction, blepharitis, rosacea, poor eyelid hygiene, and hormonal changes.
