Cranial Nerve VIII: Vestibulocochlear




Fig. 19.2 Oblique sagittal T2W (CSF bright) MRI image through the porus acusticus (opening of the IAC) demonstrates the vestibulocochlear nerve (arrow) inferior and posterior to the facial nerve

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Fig. 19.3 Oblique sagittal T2W (CSF bright) MRI image through the midportion of the IAC demonstrates the cochlear nerve (arrow) inferiorly and anteriorly. The facial nerve is seen superiorly and anteriorly within the IAC, superior to the cochlear nerve, reminding us of the memory phrase, “7-up, coke-down” (facial nerve up and cochlear nerve down), describing the position of these two nerves within the lateral IAC. The posterior superior and inferior vestibular nerves are separating at this midpoint posteriorly within the IAC

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Fig. 19.4 Axial thin section magnified T2W (CSF bright) MRI image through the IAC demonstrates the cochlear nerve (arrow) anteriorly within the IAC, extending toward the bowtie-shaped modiolus within the center of the cochlea

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19.2 Function






  • Special sensory function (SA):



    • Cochlear nerve: Transmits auditory sensory information from the cochlea to the brain


    • Vestibular nerve: Transmits balance and spatial orientation information from the vestibule and semicircular canals to the brain. Increases tone in antigravitary extensors and holds eyes on target while the head moves.


19.3 Pathology


Individual symptoms: Sensorineural hearing loss, pulsatile or nonpulsatile tinnitus, and vertigo [4]. Damage to the vestibulocochlear nerve results in the following symptoms depending on location:

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Dec 24, 2017 | Posted by in NEUROSURGERY | Comments Off on Cranial Nerve VIII: Vestibulocochlear

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