Which history finding best supports suspected superior canal dehiscence when vertigo is triggered by sound or pressure?

• A. No response to auditory stimuli.
• B. Vertigo or disequilibrium triggered by loud noises or pressure changes (Tullio phenomenon).
• C. Bilateral progressive loss of hearing.
• D. Purely central vertigo without auditory triggers.

Answer: (B)

When vertigo is triggered by sound or pressure, it points to a third-window abnormality in the inner ear, most classically a dehiscence of the superior semicircular canal. This thin or missing bone allows sound and pressure changes to move the inner-ear fluids more easily, directly stimulating the canal and causing vertigo—what clinicians call the Tullio phenomenon. That history best fits superior canal dehiscence because it reflects this abnormal vestibular sensitivity to acoustic energy and pressure. Other histories don’t align with this mechanism: no response to sounds suggests normal vestibular audition, bilateral progressive hearing loss points to broader or different pathology, and vertigo without auditory triggers makes a central or non–third-window peripheral cause more likely.