Question:medium
Vestibular schwannoma (acoustic neuroma) arises most frequently from:
Vestibular schwannoma (acoustic neuroma) arises most frequently from:
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It is a vestibular schwannoma, and the upper vestibular division is the classic site of origin.
Updated On: Jun 24, 2026
- Superior vestibular nerve
- Inferior vestibular nerve
- Cochlear nerve
- Facial nerve
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The Correct Option is A
Solution and Explanation
The label acoustic neuroma is somewhat misleading because the lesion is neither truly acoustic in origin nor a neuroma. It is a schwannoma, a tumour of Schwann cells, and it forms on the vestibular component of the eighth cranial nerve. That is why the preferred name is vestibular schwannoma.
The eighth nerve splits into a cochlear part for hearing and a vestibular part for balance, the latter having superior and inferior divisions. Tumour growth nearly always begins on the vestibular side rather than the cochlear side. Within the vestibular nerves, the superior division is the site most often cited as the point of origin, related to the region where peripheral Schwann cell myelin meets central glial myelin and Schwann cells proliferate most readily.
Patients still present first with hearing loss and tinnitus, because the enlarging mass compresses the neighbouring cochlear fibres inside the narrow internal auditory canal, but this is a secondary effect rather than the source. The inferior vestibular nerve can give rise to these tumours too, just less commonly, and the facial nerve is pushed aside rather than being the parent nerve. Putting this together, the superior vestibular nerve is the most frequent origin.
\[\boxed{\text{Superior vestibular nerve}}\]
The eighth nerve splits into a cochlear part for hearing and a vestibular part for balance, the latter having superior and inferior divisions. Tumour growth nearly always begins on the vestibular side rather than the cochlear side. Within the vestibular nerves, the superior division is the site most often cited as the point of origin, related to the region where peripheral Schwann cell myelin meets central glial myelin and Schwann cells proliferate most readily.
Patients still present first with hearing loss and tinnitus, because the enlarging mass compresses the neighbouring cochlear fibres inside the narrow internal auditory canal, but this is a secondary effect rather than the source. The inferior vestibular nerve can give rise to these tumours too, just less commonly, and the facial nerve is pushed aside rather than being the parent nerve. Putting this together, the superior vestibular nerve is the most frequent origin.
\[\boxed{\text{Superior vestibular nerve}}\]
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