Test-Retest Reliability, Effects of Age and Comparison of Horizontal 2 Semicircular Canals Gain Values between Head Impulse and Suppression Head Impulse Paradigms

BACKGROUND: This study investigates the test-retest reliability, aging effects, and differences in horizontal semicircular canals gain values between the head impulse paradigm and suppression head impulse paradigm. METHODS: Sixty healthy adult subjects aged 22-76-year-old (mean ± standard deviation = 47.27 ± 18.29) participated in the head impulse paradigm and suppression head impulse paradigm using the video head impulse test. The Head impulse paradigm was used to assess all 6 semicircular canals, while suppression head impulse paradigm measured only the horizontal canals. Twenty subjects aged 22-40-year-old (25.25 ± 4.9) underwent a second session for the test-retest reliability. RESULTS: There were good test-retest reliability for both measures (right horizontal head impulse paradigm, intraclass correlation coefficient = 0.80; left horizontal head impulse paradigm, intraclass correlation coefficient = 0.77; right anterior head impulse paradigm, intraclass correlation coefficient = 0.86; left anterior head impulse paradigm, intraclass correlation coefficient = 0.78; right posterior head impulse paradigm, intraclass correlation coefficient = 0.78; left posterior head impulse paradigm, intraclass correlation coefficient = 0.75; right horizontal suppression head impulse paradigm, intraclass correlation coefficient = 0.76; left horizontal suppression head impulse paradigm, intraclass correlation coefficient = 0.79). The test-retest reliability for suppression head impulse paradigmanti-compensatory saccade latency and amplitude were moderate (right latency, intraclass correlation coefficient = 0.61; left latency, intraclass correlation coefficient = 0.69; right amplitude, intraclass correlation coefficient = 0.69; left amplitude, intraclass correlation coefficient = 0.58). There were no significant effects of age on head impulse paradigm and suppression head impulse paradigm vestibulo-ocular reflex gain values and suppression head impulse paradigmsaccade latency. However, the saccade amplitude became smaller with increasing age, P < .001. The horizontal suppression head impulse paradigm vestibulo-ocular reflex gain values were significantly lower than the head impulse paradigm for both sides (right, P = .004; left, P = .004). CONCLUSION: There was good test-retest reliability for both measures, and the gain values stabilized with age. However, suppression head impulse paradigm anti-compensatory saccade latency and amplitude had lower test-retest reliability than the gain. The suppression head impulse paradigm vestibulo-ocular reflex gain was lower than the head impulse paradigm and its anti-compensatory saccade amplitude reduced with increasing age.