Title: Distichia

{{Short description|Eyelash growth from an abnormal part of the eyelid}}
{{For|the genus of plant|Distichia (plant)}}
{{Infobox medical condition (new)
| name            = Distichia
| image           = Canine distichiae.JPG
| caption         = Distichiae of the upper and lower lid of a dog
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| field           = [[Ophthalmology]]
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A '''distichia''' is an [[eyelash]] that arises from an abnormal part of the [[eyelid]]. This abnormality, attributed to a [[genetic mutation]], is known to affect dogs and humans. Distichiae usually exit from the duct of the [[meibomian gland]] at the eyelid margin. They are usually multiple, and sometimes more than one arises from a duct. They can affect either the upper or lower eyelid and are usually bilateral. The lower eyelids of dogs usually have no eyelashes.&lt;ref&gt;{{cite web | last = Brooks | first = Dennis E. | title = Ophthalmic Examination Made Ridiculously Simple | work = Proceedings of the 30th World Congress of the World Small Animal Veterinary Association | year = 2005 | url = http://www.vin.com/proceedings/Proceedings.plx?CID=WSAVA2005&amp;PID=10923&amp;O=Generic | access-date = 2007-02-20 }}&lt;/ref&gt;

Distichiae usually cause no symptoms, because the lashes are soft, but they can irritate the eye and cause tearing, squinting, inflammation, [[Corneal ulcers in animals|corneal ulcer]]s and scarring.&lt;ref&gt;{{cite web | title = Eyelids: Conformational Abnormalities | work = The Merck Veterinary Manual | year = 2006 | url = http://www.merckvetmanual.com/mvm/index.jsp?cfile=htm/bc/30105.htm | access-date = 2007-02-20 }}&lt;/ref&gt; Treatment options include manual removal, [[electrology|electrolysis]], [[cauterization|electrocautery]], [[Carbon dioxide laser|CO&lt;sub&gt;2&lt;/sub&gt; laser]] ablation,&lt;ref&gt;{{Cite web|url=https://www.aesculight.com/case-studies/distichia-laser-surgery/|title=There's something in his eye: CO&lt;sub&gt;2&lt;/sub&gt; surgical lasers for distichia|last=Winkler|first=Christopher|date=2020-01-06|website=Aesculight|language=en-US|orig-year=2019|access-date=2020-01-06}}&lt;/ref&gt; [[cryosurgery|cryotherapy]], and [[surgery]].

==Commonly affected breeds==
In [[veterinary medicine]], some canine breeds are affected by distichiasis more frequently than others:&lt;ref name=Gelatt_1999/&gt;
* [[Cocker Spaniel]]
* [[Dachshund]] (especially the miniature longhaired Dachshund)
* [[Bulldog]]
* [[Pekingese]]
* [[Yorkshire Terrier]]
* [[Flat-Coated Retriever]]
* [[Shetland Sheepdog]]
* [[Boxer (dog)|Boxer]]
* [[Poodle]]&lt;ref name=Gelatt_1999&gt;{{cite book|editor=Gelatt, Kirk N.|title=Veterinary Ophthalmology|edition=3rd|publisher=Lippincott, Williams &amp; Wilkins|year=1999|isbn=0-683-30076-8}}&lt;/ref&gt;

==Ectopic cilia==
An ectopic cilia is a special type of distichia usually found in younger dogs. Commonly affected breeds include Poodles, [[Golden Retriever]]s, and [[Shih Tzu]]s.&lt;ref&gt;{{cite web | last = Ketring | first = Kerry I. | title = The Top Ten Ophthalmic Mistakes | work = Proceedings of the North American Veterinary Conference | year = 2006 | url = http://www.ivis.org/proceedings/navc/2006/SAE/308.pdf?LA=1 | format = PDF | access-date = 2007-02-20 | url-status = dead | archive-url = https://web.archive.org/web/20070929094306/http://www.ivis.org/proceedings/navc/2006/SAE/308.pdf?LA=1 | archive-date = 2007-09-29 }}&lt;/ref&gt; The eyelash exits through the [[conjunctiva]] of the eyelid facing toward the eye, usually at the middle of the upper eyelid. It can cause intense pain and [[corneal ulcer]]s. Treatment is surgery or cryotherapy.{{cn|date=November 2025}}

==See also==
* [[Trichiasis]]
* [[Lymphedema distichiasis]]

==References==
&lt;references/&gt;

== External links ==
{{Medical resources
|   DiseasesDB     = 33329
|   ICD10          = {{ICD10|Q|10|3|q|10}}
|   ICD9           = {{ICD9|743.63}}
|   ICDO           =
|   OMIM           = 126300
|   MedlinePlus    =
|   eMedicineSubj  = oph
|   eMedicineTopic = 603
|   MeshID         =
}}
{{Congenital malformations and deformations of eye, ear, face and neck}}

[[Category:Dog diseases]]
[[Category:Congenital disorders of eyes]]
[[Category:Eyelash]]