VEMP using a new low-frequency bone conduction transducer

Area of Science:

• Audiology
• Neuroscience
• Vestibular System

Background:

• Vestibular evoked myogenic potentials (VEMPs) assess otolith function.
• Bone conduction (BC) stimulation offers an alternative to air conduction (AC) for VEMP testing.
• A new BC transducer (B250) with enhanced low-frequency response warrants evaluation.

Purpose of the Study:

• To evaluate the new B250 BC transducer in VEMP investigations.
• To compare cervical (cVEMP) and ocular (oVEMP) responses using BC and AC stimulation.
• To assess the B250's efficacy at 250 Hz and 500 Hz tone bursts.

Main Methods:

• Pilot study with three normal subjects.
• BC stimulation applied to mastoids (cVEMP) and mastoid/forehead (oVEMP).
• Comparison of B250 BC, conventional B81 BC, and AC stimulation.

Main Results:

• BC stimulation achieved VEMP thresholds at significantly lower hearing levels than AC (30-40 dB lower oVEMP at 250 Hz).
• The B250 transducer at 250 Hz reliably elicited cVEMP and oVEMP responses in all subjects.
• Similar BC thresholds were observed for ipsilateral and contralateral mastoid stimulation.

Conclusions:

• Vestibular evoked myogenic potential (VEMP) responses are obtainable at lower hearing levels with BC stimulation compared to AC.
• The B250 BC transducer demonstrates efficacy for both cVEMP and oVEMP, with consistent results across mastoid placements.