[Video head impulse test in peripheral vestibular diseases].

Area of Science:

• Neuroscience
• Ophthalmology
• Audiology

Background:

• The clinical head impulse test (HIT) assesses semicircular canal receptor function and vestibulo-ocular reflex (VOR) pathways.
• Accurate diagnosis of peripheral vestibular disorders is crucial for effective patient management.
• The video head impulse test (vHIT) offers a more detailed assessment of the VOR.

Purpose of the Study:

• To investigate the horizontal VOR using vHIT in patients with various peripheral vestibular disorders.
• To compare vHIT findings with clinical HIT in diagnosing VOR abnormalities.

Main Methods:

• Video head impulse test (vHIT) was used to examine horizontal semicircular canal VOR.
• A cohort of 55 patients with vestibular neuritis, vestibular schwannoma, Meniere's disease, bilateral vestibulopathy, and idiopathic sudden hearing loss with vertigo was studied.
• A control group of 20 healthy subjects was included for comparison.

Main Results:

• Abnormal vHIT findings were prevalent in vestibular schwannoma (100%), vestibular neuritis (90.9%), and bilateral vestibulopathy (86.7%).
• Meniere's disease (40.0%) and idiopathic sudden hearing loss with vertigo (38.5%) also showed abnormal vHIT results.
• Refixation saccades (covert and overt) were observed in cases with abnormal VOR, with isolated covert saccades being detectable only by vHIT.

Conclusions:

• vHIT, by assessing both gain and refixation saccades, accurately detects VOR changes in peripheral vestibular disorders.
• The identification of isolated covert saccades by vHIT is critical, as these can be missed by the clinical HIT.
• Failure to utilize vHIT may lead to misdiagnosis of peripheral vestibular disorders.