Quantitative analysis of gains and catch‐up saccades of video‐head‐impulse testing by age in normal subjects. (9th February 2016)

• Record Type: Journal Article
• Authors: Yang, C.J.; Lee, J.Y.; Kang, B.C.; Lee, H.S.; Yoo, M.H.; Park, H.J.
• Is Part Of: Clinical otolaryngology. Volume 41:Number 5(2016:Oct.)
• Page Start: 532
• Page End: 538
• Publication Date: 2016-02-09
• Subjects: Otolaryngology -- Periodicals; 617.51005
• DOI: 10.1111/coa.12558
• Languages: English
• ISSNs: 1749-4478

Abstract

Abstract : Objectives: To evaluate video‐head‐impulse test (vHIT) results in normal subjects, to determine the normative values of vHIT for the vestibulo‐ocular reflex (VOR) and to characterise the catch‐up saccades (CSs). Design: Prospective cohort study. Setting: Tertiary care academic referral centre. Participants: Fifty healthy subjects with no history of vestibular impairment, ten each in their 20's, 30's, 40's, 50's and 60's, underwent vHITs in the lateral semicircular canal plane. Main outcome measures: vHIT gains and the incidence and amplitudes of covert and overt CSs. Results: The mean vHIT gain was 1.02 ± 0.07, and the mean gain asymmetry was 2.39 ± 1.96%, with no significant differences among age groups. CSs were observed during 22.6% of the trials and in 49% of the ears. The incidence of CSs was not associated with age. The mean velocity of CSs was 55.5 ± 16.9°/s, and its mean interaural difference was 11.8 ± 10.7°/s. Conclusions: vHIT gains were consistently equal to 1.0 in all age groups (20's to 60's), suggesting that abnormal criteria for vHIT gain (e.g. 0.8) and gain asymmetry (e.g. 8%) can be used, regardless of age. CSs were observed in about half of normal ears, suggesting that VOR is a hypometric system. The amplitudes and interaural difference of CSs were also similar in all age groups, suggesting that abnormal criteria for CS amplitude (e.g. 100°/s) and interaural difference (e.g. 40°/s) can be used, regardless of age.