Premium
Quantitative analysis of gains and catch‐up saccades of video‐head‐impulse testing by age in normal subjects
Author(s) -
Yang C.J.,
Lee J.Y.,
Kang B.C.,
Lee H.S.,
Yoo M.H.,
Park H.J.
Publication year - 2016
Publication title -
clinical otolaryngology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.914
H-Index - 68
eISSN - 1749-4486
pISSN - 1749-4478
DOI - 10.1111/coa.12558
Subject(s) - medicine , audiology , reflex
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 ( CS s). 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 vHIT s in the lateral semicircular canal plane. Main outcome measures vHIT gains and the incidence and amplitudes of covert and overt CS s. 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. CS s were observed during 22.6% of the trials and in 49% of the ears. The incidence of CS s was not associated with age. The mean velocity of CS s 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. CS s were observed in about half of normal ears, suggesting that VOR is a hypometric system. The amplitudes and interaural difference of CS s 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.