noun, plural: meibomian glands
A sebaceous gland in the tarsal plate in the eyelid and secretes meibum oil that acts as a hydrophobic barrier to prevent tears from readily spilling onto the cheek and from evaporation of the tear film in the eye
The meibomian gland is a sebaceous gland that is found in the tarsal plate inside the eyelid. Thus, the meibomian gland is also called the tarsal gland. It secretes meibum, an oily substance. It acts as a hydrophobic barrier at the rim of the eyelid. The oil coats the aqueous layer. This helps prevent the evaporation of the tear film in the eye. It also helps prevent the tears from readily spilling onto the cheek. In humans, there are about fifty glands on the upper eyelids and 25 glands on the lower eyelids. A dysfunctional meibomian gland results in dry eye disease and blepharitis. Inflammed meibomian gland is referred to as meibomitis.
The meibum is one of the components of tear. The other components are mucins secreted by the conjunctival goblet cells and the lacrimal fluid secreted by the lacrimal glands. The meibum is comprised mainly of lipids and proteins.
Word origin: named after Heinrich Meibom, a German anatomist
- tarsal gland
- palpebral gland