Vestibular aqueduct

Vestibular aqueduct
Interior of right osseous labyrinth.
The cochlea and vestibule, viewed from above. (Aqueductus vestibuli labeled at bottom right.)
Details
Identifiers
Latin	Aquaeductus vestibuli
MeSH	A09.246.631.909.957
Dorlands /Elsevier	a_55/12148745
TA	A15.3.03.057
FMA	77821
Anatomical terminology []

At the hinder part of the medial wall of the vestibule is the orifice of the vestibular aqueduct, which extends to the posterior surface of the petrous portion of the temporal bone.

It transmits a small vein, and contains a tubular prolongation of the membranous labyrinth, the ductus endolymphaticus, which ends in a cul-de-sac, the endolymphatic sac, between the layers of the dura mater within the cranial cavity.

Enlargement of the vestibular aqueduct to greater than 2 mm is associated with enlarged vestibular aqueduct syndrome, a disease entity that is associated with one-sided hearing loss in children. The diagnosis can be made by high resolution CT or MRI, with comparison to the adjacent posterior semicircular canal. If the vestibular aqueduct is larger in size, and the clinical presentation is consistent, the diagnosis can be made. Treatment is with mechanical hearing implants. There is an association with Pendred syndrome and incomplete cochlear partition (so called "Mondini dysplasia").

Base of the skull. Upper surface.

Temporal bone

This article incorporates text in the public domain from the 20th edition of Gray's Anatomy (1918)