Measured upper eyelash length of 12 mm or greater, and/or increased length, thickness, curl, pigmentation of lashes
Trichomegaly is a condition in which the eyelashes are abnormally long,[1] objectively defined as 12mm or greater in the central area and 8mm in the peripheral.[2] The term was first used by H. Gray in 1944 in a publication in the Stanford Medical Bulletin,[2] though he was only the third person to characterize the disorder; the first two reports were published in German in 1926 and 1931 by Reiter and Bab, respectively.[3] Gray suggested the use of the term "movie lashes" to describe this condition, for long lashes were at the time being portrayed in film as a desirable characteristic in women.
The condition does not always present a medical issue and can sometimes be a benign familial or isolated trait. The presence of excessively long or lush lashes in healthy individuals is likely under-reported as it is an aesthetically pleasing facial feature and usually does not prompt diagnosis or treatment on its own.[2]
The objective definition of eyelash trichomegaly is having lashes which measure 12 mm or longer. However, lashes displaying increased curl, pigmentation, and thickness have also been included in the diagnosis of the condition.[2]
