Acoustic neuroma (vestibular schwannoma) most commonly arises from which division of the vestibulocochlear nerve?

• A Cochlear division, at the spiral ganglion
• B Superior vestibular nerve, at the Scarpa's ganglion ✓
• C Inferior vestibular nerve, at the saccular macula
• D Cochlear and vestibular equally in 50:50 ratio

Explanation

Vestibular schwannomas most commonly arise from the superior vestibular nerve (about 60-70% of cases), followed by the inferior vestibular nerve (~15%) and combined divisions. They arise from Schwann cells at the Obersteiner-Redlich zone — the transition from central (CNS) to peripheral (PNS) myelin — located at the internal auditory meatus. The cochlear nerve is much less commonly the site of origin. Scarpa's ganglion (vestibular ganglion) in the internal auditory canal is the location of the cell bodies of vestibular neurons.

Reference: Dhingra Diseases of Ear, Nose and Throat, 7th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.