A patient with Meniere's disease undergoes cervical VEMP (cVEMP) testing. In this test, a large P1-N1 amplitude on the affected side compared to the normal side is most consistent with:

• A Superior semicircular canal dehiscence
• B Vestibular neuritis affecting inferior vestibular nerve
• C Benign paroxysmal positional vertigo
• D Saccular hydropic dilation increasing sensitivity of saccular hair cells ✓

Explanation

cVEMP tests saccular function via the inferior vestibular nerve, measuring inhibitory responses in the sternocleidomastoid muscle. In endolymphatic hydrops (Meniere's disease), the saccule is dilated and its hair cells are hypersensitive to sound. This results in enhanced (larger amplitude) cVEMP responses on the affected side, in contrast to the reduced amplitudes seen in other vestibular pathologies where the saccule or nerve is damaged. Superior canal dehiscence also produces enhanced VEMPs but via a different mechanism (third-window effect).

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.