In some patients, meibum may be produced but, for a variety of reasons, it does not flow onto the tear film, resulting in evaporative dry eye.
The International Workshop on Meibomian Gland Dysfunction: report of the Subcommittee on Anatomy, Physiology, and Pathophysiology of the meibomian gland
Knop E, Knop N, Millar T, Obata H, Sullivan DA.
Investigative Ophthalmology and Visual Science
2011 Mar 30;52(4):1938-78. doi: 10.1167/iovs.10-6997c. Print 2011 Mar. PMID:21450915
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