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The usefulness of the video head impulse test in children and adults post-concussion.

OBJECTIVE
Dizziness after concussion have been reported in both youths and adults. It is not clear if the dizziness experienced post-concussion is from peripheral or central etiology. New technology has been developed to quickly and easily quantify the magnitude of peripheral vestibular disorders that is non-invasive and acceptable to youths and adults. The purpose of this study was to determine if youths and adults' post-concussion have evidence of decreased horizontal semicircular canal vestibulo-ocular reflex (VOR) gains as measured with the video head impulse test (vHIT), which would indicate a peripheral vestibular disorder. An additional purpose was to determine if VOR gain scores correlate with functional performance measures.


DESIGN
Descriptive cross sectional.


SETTING
Large medical center out-patient concussion program.


PARTICIPANTS
Fifty-six subjects with concussion.


MAIN OUTCOMES/MEASURES
Subjects completed the vHIT testing, the Dizziness Handicap Inventory (DHI), the Vestibular Activities and Participation (VAP) scale, the Pediatric Vestibular Symptom Questionnaire, gait speed assessment, the Dynamic Gait Index (DGI) and a verbal analog scale of symptom provocation before and after the vHIT testing.


RESULTS
There were no abnormal vHIT findings in any subject. Headaches, dizziness and nausea were significantly worse post vHIT testing (p < 0.05). Youths had better DGI and DHI scores than subjects older than 20 (p < 0.05).


CONCLUSION
The vHIT did not detect horizontal semicircular canal weakness in any of the subjects tested. In addition, older adults reported more activity and participation limitations than the younger subjects with concussion.