Eyelash

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For other uses, see Eyelash (disambiguation).
Eyelash
N2 Human eye.jpg
Human eyelashes
Details
Latin Cilia
Identifiers
TA A15.2.07.037
FMA FMA:53669
Anatomical terminology

An eyelash or simply lash is one of the hairs that grow at the edge of the eyelid. Eyelashes protect the eye from debris and perform some of the same function as whiskers do on a cat or a mouse in the sense that they are sensitive to being touched, thus providing a warning that an object (such as an insect or dust mite) is near the eye (which then closes reflexively).

The Greek word for eyelash is "blepharo", which is often used as a root in biological terms like Blephara and Katoblephara.

Structure[edit]

Development[edit]

The eyelashes of the embryo develop from the ectoderm[1] between the 22nd and 26th week of pregnancy.[2] Eyelashes take about seven to eight weeks to grow back if pulled out but constant pulling can lead to permanent damage. Their color may differ from that of the hair, although they tend to be dark on someone with dark hair and lighter on someone with light hair.

Glands[edit]

The follicles of eyelashes are associated with a number of glands known as the glands of Zeis and the glands of Moll.

Clinical significance[edit]

A stye

There are a number of diseases or disorders involving the eyelashes:

Eyelash and eyebrow transplant surgeries may be help to reconstruct or thicken lashes or eyebrow hair.

Society and culture[edit]

Cosmetics[edit]

Green mascara

Long eyelashes are considered a sign of beauty in many cultures. Accordingly, some women seek to enhance their eyelash length artificially, using eyelash extensions. On the other hand, Hadza women are known to trim their own eyelashes.[3]

Kohl, a black putty (usually antimony sulfide or lead sulfide), has been worn as far back as the Bronze Age to protect and enhance lashes. In Ancient Egypt, it was used as well by the wealthy and the royal to protect their eyes from the sand, dust, and bugs. Modern eye makeup includes mascara, eyeliner, eye putty, and eye shadow to emphasize the eyes. The twentieth century saw the beginning of convincing false eyelashes, popular in the 1960s. There are also different tools that can be used on the lashes such as eyelash curler or mascara shield (also named mascara guard or eye makeup helper).

Permanent eyelash tints and eyelash extensions have also become popular procedures, even in fairly basic salons. It is also possible to get eyelash transplants, which are similar in nature to hair transplantation often done on the head. Since the hair is transplanted from the hair on the head, the new eyelashes will continue to grow like head hair and will need to be trimmed regularly.[4]

Latisse was introduced in the first quarter of 2009 by Allergan as the first drug to receive FDA approval for eyelash growth. Latisse is a solution of bimatoprost, the active component of the glaucoma medication Lumigan. According to Allergan, noticeable eyelash growth occurs within 16 weeks. Growth is reported to occur primarily on the upper eyelashes. In addition, the past decade has seen the rapid increase in the development of eyelash conditioners. These conditioners are designed to increase the health and length of your lashes. Many utilize seed extract, minerals, and other chemicals to achieve these results.[citation needed]

In other animals[edit]

A horse's eye, showing lashes

Lashes, being hair, are found in mammals. Camels' lashes are remarkably long and thick. Horses, cows, and also ostriches (vestigial feathers without barbs) feature eyelashes as well. Inherited eyelash problems are common in some breeds of dogs as well as horses.

Eyelash vipers show a set of modified scales over the eyes which look much like eyelashes. Hornbills have prominent feather eyelashes, an uncommon feature in birds.

References[edit]

  1. ^ Standring, Susan Neil R. Borley (2008). Gray's Anatomy: the Anatomical Basis of Clinical Practice (40th ed.). Edinburgh: Churchill Livingstone/Elsevier. p. 703. ISBN 978-0443066849. 
  2. ^ "Fetal development: MedlinePlus Medical Encyclopedia". Nlm.nih.gov. Retrieved 2013-03-16. 
  3. ^ "Hadza". Encyclopedia of Sex and Gender: Men and Women in the World's Cultures, Vol. 1. New York: Springer. 2003. ISBN 978-0-306-47770-6. 
  4. ^ "Plug and sew eyelashes for women". Xinhua News. 25 October 2006. Retrieved 2013-03-16. 

External links[edit]

Do Eyelashes Grow Back