Video Head Impulse Test Can Reveal Silent Vestibular Dysfunction in Normal-Hearing Individuals With Tinnitus

Area of Science:

• Neuroscience
• Otolaryngology
• Vestibular System Research

Background:

• Tinnitus can signal early cochleovestibular issues even in normal-hearing individuals.
• The Head Impulse Paradigm (HIMP) and Suppression Head Impulse Paradigm (SHIMP) assess vestibular function.

Purpose of the Study:

• To characterize HIMP and SHIMP performance in normal-hearing individuals with tinnitus.
• To investigate potential subclinical vestibular deficits in this population.

Main Methods:

• Compared HIMP and SHIMP vestibulo-ocular reflex (VOR) gains and saccadic patterns in 45 normal-hearing individuals with unilateral tinnitus and 45 controls.
• Measured interaural VOR gain asymmetry and saccade presence/absence.

Main Results:

• Individuals with tinnitus exhibited significantly reduced VOR gains in the affected ear during both HIMP and SHIMP compared to controls and their non-tinnitus ear.
• Higher interaural VOR gain asymmetry was observed in the tinnitus group.
• Distinct anticompensatory saccade patterns were noted in individuals with tinnitus, with a negative correlation between tinnitus duration and VOR gain.

Conclusions:

• The VOR and its suppression are impaired in normal-hearing individuals with tinnitus.
• Reduced VOR gains and altered saccades suggest subtle peripheral vestibular involvement.
• HIMP and SHIMP paradigms show promise for detecting subclinical vestibular deficits in tinnitus patients.