External auditory canal
Last reviewed: 23.04.2024
All iLive content is medically reviewed or fact checked to ensure as much factual accuracy as possible.
We have strict sourcing guidelines and only link to reputable media sites, academic research institutions and, whenever possible, medically peer reviewed studies. Note that the numbers in parentheses ([1], [2], etc.) are clickable links to these studies.
If you feel that any of our content is inaccurate, out-of-date, or otherwise questionable, please select it and press Ctrl + Enter.
The external ear canal (meatus acusticus externus), open from the outside, ends blindly in the interior, separating from the middle ear cavity by the tympanic membrane. The length of the ear canal in an adult is an average of 35 mm, the diameter reaches 9 mm at the beginning and 6 mm in the narrowest place, where the cartilaginous external auditory canal passes into the bone. The cartilaginous external auditory meatus, which is a continuation of the auricle, has the form of a groove open upward, and is 1/5 the length of the entire ear canal. Two-thirds of the external auditory meatus have bone walls belonging to the temporal bone.
The auditory canal is S-shaped, predominantly in the horizontal plane. To straighten it, when examining the tympanic membrane, the auricle should be pulled backward and upward. The auditory meatus is lined with skin, which, thinner, continues on the eardrum. In the skin covering the cartilaginous part of the ear canal, a lot of sebaceous and a special kind of glandula ceruminosae (sulfuric glands), producing earwax.