不同头动速度对健康人群视频头脉冲前庭眼反射增益的影响

目的研究视频头脉冲试验中不同头动速度对前庭眼反射增益的影响。方法对50名健康受试者应用视频头脉冲试验仪进行测试,以不同头动速度(50°/s-100°/s、101°/s-150°/s、151°/s-200°/s、201°/s-250°/s、251°/s-300°/s)将前庭眼反射增益值分组,分析头动速度对增益的影响。结果水平半规管平均增益按不同头动速度组(50°/s-100°/s、101°/s-150°/s、151°/s-200°/s、201°/s-250°/s、251°/s-300°/s)分别为0.992±0.130、0.983±0.154、0.999±0.151、0.945±0.142、0.835±0.106,其中201°/s-250°/s组与101°/s-150°/s组(P<0.05,P=0.035)、151°/s-200°/s组(P<0.01,P=0.000)差异显著,251°/s-300°/s组和其他组别间差异均显著(P1<0.01,P1=0.000;P2<0.01,P2=0.000;P3<0.01,P3=0.000;P4<0.05,P4=0.010);前半规管平均增益按不同头动速度组分别为0.984±0.136、0.916±0.181、0.926±0.179、0.895±0.169、0.863±0.174,其中50°/s-100°/s组和101°/s-150°/s组(P<0.05,P=0.018)、201°/s-250°组(P<0.01,P=0.005)间VOR增益差异显著;后半规管平均增益按不同头动速度组(50°/s-100°/s、101°/s-150°/s、151°/s-200°/s、201°/s-250°/s、251°/s-300°/s)分别为0.997±0.158、0.846±0.156、0.793±0.130、0.815±0.112、0.830±0.046,50°/s-100°/s组和101°/s-150°/s组(P<0.01,P=0.000)、151°/s-200°/s组(P<0.01,P=0.000)、201°/s-250°/s组(P<0.01,P=0.000)间差异显著,101°/s-150°/s组和151°/s-200°/s组间差异显著(P<0.01,P=0.001)。结论前庭眼反射增益随头动速度的提高呈现递减的趋势,其中部分组别存在显著差异,实际操作中应避免头动速度过低导致的结果误判。

Effects of Head Velocity On Vestibular-Ocular Reflex Gain In Video Head Impulse Test In Healthy Subjects

Objective To report effects of head velocity on vestibular-ocular reflex gain in video head impulse test.Methods Video head impulse test(vHIT)was performed on 50 healthy subjects at different head velocities(50°/s-100°/s,101°/s-150°/s,151°/s-200°/s,201°/s-250°/s and 251°/s-300°/s).Vestibular-ocular reflex(VOR)gain values were used to analyze the effect of the head velocity.Results The VOR gain for the horizontal semicircular canal was0.992±0.130,0.983±0.154,0.999±0.151,0.945±0.142 and 0.835±0.106 for head velocity at 50°/s-100°/s,101°/s-150°/s,151°/s-200°/s,201°/s-250°/s and 251°/s-300°/s,respectively,with a significant difference between 201°/s-250°/s and101°/s-150°/s(P=0.035)and 151°/s-200°/s(P=0.000),and between 251°/s-300°/s and other head velocities(P=0.000,P=0.000,P=0.000 and P=0.010,respectively).For the anterior semicircular canal,the VOR gain was 0.984±0.136、0.916±0.181、0.926±0.179,0.895±0.169 and 0.863±0.174 for the different head velocities,respectively,with a significant difference between 50°/s-100°/s and 101°/s-150°/s(P=0.018)and 201°/s-250°/s(P=0.005).For the posterior semicircular canal,the VOR gain was 0.997±0.158,0.846±0.156,0.793±0.130,0.815±0.112 and 0.830±0.046 or the different head velocities,respectively,with a significant difference btween 50°/s-100°/s and 101°/s-150°/s(P=0.000),151°/s-200°/s(P=0.000)and 201°/s-250°/s(P=0.000),and between 101°/s-150°/s and 151°/s-200°/s(P=0.001).Conclusion The VOR gain in vHIT is reduced as head velocity is increased.Clinicians need to be aware of the possibility of misinterpretation when head velocity is extremely slow in clinical practice.