External acoustic meatus
1735374
224167242
2008-07-07T17:02:26Z
Useight
2910303
Reverted edits by [[Special:Contributions/87.244.104.169|87.244.104.169]] to last version by Useight (using [[WP:HG|Huggle]])
{{Infobox Anatomy |
Name =External acoustic meatus
|
Latin = meatus acusticus externus |
GraySubject = 229 |
GrayPage = 1036 |
Image = Ear-anatomy-text-small.png |
Caption = Anatomy of the human ear. |
Image2 = |
Caption2 = |
Precursor = groove (cleft) of the [[first branchial arch]].<ref>{{EmbryologyUNC|hednk|022}}</ref> |
System = |
Artery = [[Anterior auricular branches of superficial temporal artery|anterior auricular branches]] |
Vein = |
Nerve = |
Lymph = |
MeshName = |
MeshNumber = |
DorlandsPre = m_06 |
DorlandsSuf = 12518132 |
}}
The '''ear canal''' ('''external auditory meatus''', '''external acoustic meatus'''), is a tube running from the [[outer ear]] to the [[middle ear]]. The human ear canal extends from the [[pinna (anatomy|pinna]] to the [[eardrum]] and is about 26 [[millimeter|mm]] in length and 7 mm in diameter.
== Size and shape ==
The human ear canal is approximately 26 mm long and 7 mm in diameter. Size and shape of the canal vary among individuals. This is an important factor to consider when fitting [[hearing protectors]].
==Disorders==
The ear canal, because of its relative exposure to the outside world, is a common victim of diseases and other disorders. Some disorders include:
* [[Otitis externa]] (swimmer's ear), bacteria-caused inflammation of the ear canal
* [[Contact dermatitis]] of the ear canal
* Ear fungus
* Ear [[myiasis]], an extremely rare infestation of maggots
* Bone exposure, caused by the wearing away of skin in the canal
*[[Granuloma]], a [[scar]] usually caused by [[tympanostomy tube|tympanostomy tubes]]
*[[Stenosis]], a gradual closing of the canal
*Foreign body in ear
*[[Ear mite]]s in animals.
==Earwax==
{{Main|Earwax}}
Earwax, also known as cerumen, is a yellowish, waxy substance secreted in the ear canals. It plays an important role in the human ear canal, assisting in cleaning and lubrication, and also provides some protection from [[bacterium|bacteria]], [[fungus|fungi]], and [[insect]]s. Excess or impacted cerumen can press against the eardrum and/or occlude the external auditory canal and impair hearing.
==References==
<references/>
==Additional images==
<gallery>
Image:Gray187.png|Base of skull. Inferior surface.
Image:Gray189.png|Left infratemporal fossa.
Image:Gray907.png|External and middle ear, opened from the front. Right side.
Image:Gray908.png|Horizontal section through left ear; upper half of section.
</gallery>
== External links ==
*[http://www.nchpdp.med.va.gov/MonthlyPreventionTopics/2004_08/HowYourEarWorks.doc Veterans Health Administration web site]
*[http://www.osha.gov/dts/osta/otm/noise/health_effects/physiology.html OSHA web site]
*[http://www.entusa.com/external_ear_canal.htm Continuing Medical Education Ear Photographs]
*[http://www.bris.ac.uk/Depts/ENT/otoscopy_tutorial.htm Otoscopy Tutorial w/ Images]
* {{RocheLexicon|34257.000-1}}
{{Auditory system}}
{{Foramina of skull}}
[[Category:Auditory system]]
[[de:Äußerer Gehörgang]]
[[et:Kuulmekäik]]
[[es:Conducto auditivo externo]]
[[lt:Klausomoji landa]]
[[nl:Gehoorgang]]
[[no:Øregang]]
[[pl:Przewód słuchowy zewnętrzny]]
[[fi:Korvakäytävä]]