The meibomian glands are located in the eyelids. Secretions from these glands comprise the lipid layer of the tear film which is crucial in preventing rapid evaporation of the tears. Failure of these glands to produce or secrete oil due to chronic blockage, thickening of the meibum, etc. will affect the quality and stability of the tear film.
Meibomian Gland Dysfunction is quite common and unfortunately it often goes undiagnosed. Even when diagnosed is often not treated or is not treated effectively until it has become chronic or severe. Meibomian Gland Dysfunction may be inflammatory (often as a result of blepharitis) or atrophic.
Common symptoms (which may vary) include: itching, burning, scratchiness, excessive tearing, crusty scaling around the eyelashes and foreign body sensation.