Video Head Impulse Testing in a Pediatric Population: Normative Findings

Area of Science:

• Vestibular science
• Ophthalmology
• Pediatric audiology

Background:

• The video head impulse test (vHIT) assesses all six semicircular canals (SCCs) by measuring vestibulo-ocular reflex (VOR) gain.
• While vHIT is validated in adults, normative data for children, especially for vertical canals, is limited.

Purpose of the Study:

• To characterize normal vHIT responses for all six SCCs in children aged 4-12 years.
• Establish normative VOR gain values for pediatric populations.

Main Methods:

• A cross-sectional prospective descriptive study involving 41 participants aged 4-12 years and adults.
• vHIT was performed using the ICS Impulse system, measuring VOR gain for lateral, anterior, and posterior SCCs.
• Pediatric VOR gain was compared to adult VOR gain across all SCCs.

Main Results:

• No significant VOR gain differences were found between pediatric age groups; data were combined for comparison with adults.
• Pediatric participants showed significantly higher VOR gain for left lateral SCC but significantly lower gain for left anterior and right posterior (LARP) SCCs compared to adults.
• Increased age correlated with decreased test time; significant variability was noted in right anterior and left posterior (RALP) testing, partly due to pupil size.

Conclusions:

• vHIT is effective for assessing lateral SCC function in children as young as 4 years, providing normative data.
• Modified gain cutoffs are suggested for LARP and RALP testing in children due to observed variability and lower gain.
• Further research is needed to validate LARP and RALP response reliability in children, with discussed pediatric modifications for vHIT administration.