Inner ear canal
The paired internal auditory canal ( Meatus acusticus internus ) runs in the temporal bone from back to front and is part of the inner ear . In an adult human, it is about 1 cm long. Its funnel-shaped opening into the posterior cranial fossa is known as Porus acusticus internus .
Input of the inner ear canal unite the vestibular nerve and the cochlear nerve to vestibulocochlear nerve . It also serves to pass through the facial nerve (VII. Cranial nerve ), including the intermedius nerve . In addition, blood vessels , the Vasa labyrinthi, also pass through the internal auditory canal . In the depth of the inner auditory canal, the fundus meatus acustici interni , a transverse ridge ( Crista transversa ) and two weaker vertical ridges ( Cristae verticales superior et inferior ) divide the interior into four quadrants. The anterior upper quadrant is used for the passage of the facial nerve. In the two anterior vertical sections, the utriculoampullary nerve and the saccular nerve initially form a ganglion , then unite to form the vestibular nerve, which in turn runs with the cochlear nerve into the larger lower quadrant.
The three meninges also continue into the inner auditory canal . The dura mater lies directly against the bone, the pia mater envelops the nerve cords. As in the brain, between the arachnoid and pia mater lies a subarachnoid space filled with cerebrospinal fluid .
Individual evidence
- ↑ a b c Walther Graumann, Dieter Sasse: Compact textbook anatomy . tape 4 . Schattauer, Stuttgart 2005, ISBN 978-3-7945-2064-0 , pp. 122 .