Title: Trichiasis

{{Short description|Abnormally positioned eyelashes that grow back toward the eye}}
{{Infobox medical condition (new)
| name            = Trichiasis
|
| synonyms        = 
| symptoms        =
| complications   =
| onset           =
| duration        =
| types           =
| causes          =
| risks           =
| diagnosis       = [[Slit lamp]]
| differential    =
| prevention      =
| treatment       =
| medication      =
| prognosis       =
| frequency       =
| deaths          =
}}
'''Trichiasis''' ({{IPAc-en|t|r|ɪ|k|i|ˈ|eɪ|s|ɪ|s}} {{respell|trik|ee|AY|sis}}, {{IPAc-en|t|r|ɪ|ˈ|k|aɪ|ə|s|ɪ|s}} {{respell|tri|KEYE|ə|sis}})&lt;ref&gt;{{cite web |url=https://www.lexico.com/definition/trichiasis |archive-url=https://web.archive.org/web/20210410143656/https://www.lexico.com/definition/trichiasis |archive-date=April 10, 2021 |title = TRICHIASIS {{!}} Meaning &amp; Definition for UK English {{!}} Lexico.com}}&lt;/ref&gt; is a medical term for abnormally positioned [[eyelash]]es that grow back toward the eye, touching the [[cornea]] or [[conjunctiva]]. This can be caused by [[infection]], [[inflammation]], [[autoimmune]] conditions, congenital defects, eyelid [[agenesis]] and [[Physical trauma|trauma]] such as burns or eyelid injury.

Standard treatment involves removal or destruction of the affected eyelashes with [[electrology]], specialized [[laser]], or [[surgery]].  In many cases, removal of the affected eyelashes with forceps resolves the symptoms, although the problem often recurs in a few weeks when the eyelashes regrow.  Severe cases may cause scarring of the cornea and lead to vision loss if untreated.  Mild cases may not require treatment.

Repeated cases of [[trachoma]] infection may cause trichiasis.&lt;ref name=&quot;Rabiu&quot;&gt;{{cite journal |vauthors= Rabiu M, Alhassan MB, ((Ejere HOD)), Evans JR |title= Environmental sanitary interventions for preventing active trachoma |journal=Cochrane Database Syst Rev|volume=2012 |article-number= CD004003 |date=2012 |issue= 2 |pmid= 22336798|doi= 10.1002/14651858.CD004003.PUB4|pmc=4422499}}&lt;/ref&gt;

Posterior misdirection of normal lashes most frequently affects the lower lid.

==In dogs==
Trichiasis in [[dog]]s is hair from the eyelid growing in the wrong direction and rubbing on the eye, causing irritation.  It usually occurs at the lateral upper eyelid, especially in the [[English Cocker Spaniel]].&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;  Trichiasis also refers to hair from a nasal fold rubbing on the eye.  This type of trichiasis can be flattened by rubbing [[petroleum jelly]] onto it, but surgery is sometimes necessary for permanent correction.{{cn|date=November 2025}}

==Complications==
* Inferior punctate epitheliopathy
* Corneal ulceration
* [[Pannus]]

==See also==
* [[Distichiasis]]
* [[Madarosis]]
* [[Trachoma]]

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

== External links ==
{{Medical resources
|   DiseasesDB     = 31305
|   ICD10          = {{ICD10|H|02|0|h|00}} ([[ILDS]] H02.010) 
|   ICD9           = {{ICD9|374.05}}
|   ICDO           =
|   OMIM           =
|   MedlinePlus    =
|   eMedicineSubj  = oph
|   eMedicineTopic = 609
|   MeshID         = D058457
}}

{{Eye pathology}}

[[Category:Dog diseases]]
[[Category:Disorders of eyelid, lacrimal system and orbit]]
[[Category:Eyelash]]