목적: The Video-Head Impulse Test (vHIT) is a new tool that allows recordings of eye and head velocities to determine the gain of the vestibulo-ocular reflex (VOR) as well as the temporal onset and the amplitudes of corrective saccades in relation to the head movements. Catch-up saccades are compensatory eye movement to recover the impaired eye movement by vestibular hypofunction. There has been no study showing normative values according to age and we wanted to investigate VOR gain and characterize the covert and overt catch-up saccades at different age groups. 방법:vHIT test was performed in the lateral semicircular canal plane from 50 healthy subjects with no history of vestibular or neurologic impairment (10 patients at each 5 age groups; 20's, 30's, 40's, 50's, and above 60) were investigated. The vHIT gains, the incidence and amplitudes of covert and overt catch-up saccades were analyzed. 결과:Mean values of vHIT gains were 1.10±0.11, 0.98±0.10, 0.96±0.14, 1.02±0.07, 1.08±0.20 in the age groups of twenties, thirtes, forties, fifties, and above sixties, respectively. Covert saccades were revealed in 4%, 20%, 35%, 22%, and 22%, whereas overt saccades in 95%, 55%, 25%, 70%, and 70%, and combination of overt or covert saccades were found in 100%, 70%, 75%, 80%, and 75%. Mean peak velocity of covert saccades were 24.9±8.2, 26.4±20.8, 54.3±16.3, 67.0±26.1, and 25.5±9.7 deg/s, mean peak velocity of overt saccade were 40.1±7.9, 44.4±17.4, 37.8±6.1, 52.0±11.6, and 42.8±20.4 deg/s and mean peak velocity of combination of overt or covert saccades were 39.3±8.9, 46.6±16.6, 52.4±15.9, 63.0±19.8, and 42.1±20.2 deg/s. The interaural amplitude differences of saccades at each age group were 7.9±6.0, 6.6±8.5, 13.8±11.4, 13.6±8.7, and 12.7±14.3°/sec. 결론:Although the vHIT gains were equal to 1.0 at all age groups, compensatory saccades could be found most of them regardless of the age. The amplitudes of saccades tended to increase upto 100 deg/s as a function of age, and interaural amplitude difference of saccades kept consistently low, which could be used as an criterion to differentialte normal and abnormal results.