速度阶跃试验的新认知

New Insights into Velocity Step Test in Vestibular Function Assessment

速度阶跃试验(velocity step test,VST)是一种评估前庭功能的旋转试验,能够反映水平半规管前庭眼反射功能和速度存储机制。我们对VST的机制、检查方法、临床表现及影响因素进行了综述。在VST中,衰减时间常数(time constant,Tc)与峰值增益是两个主要参数,较短的Tc常见于单侧或双侧外周病变,而较长的Tc可能与中枢处理缺陷有关。虽然峰值增益重要性略逊于Tc,但其可以为Tc提供补充信息。Tc与正弦谐波加速试验的相位可进行换算,这两种方法可在临床上互为补充。在实际应用中,Tc会受到检查顺序、转椅速度、头部位置、适应性和警觉性、乙醇作用和视觉条件等因素的影响。目前,VST在前庭领域的研究主要限于描述前庭双温和晕动症的表现,对于其在其他领域的应用,仍需要进一步的研究。

The velocity step test(VST) is a rotary test that evaluates vestibular function,reflecting the function of the horizontal vestibular-ocular reflex and the velocity storage mechanism.This paper reviews the examination mechanism,clinical manifestations,examination,and influencing factors related to VST.In VST,the time constant(Tc) and peak gain are the two primary parameters.A short Tc is commonly associated with unilateral or bilateral peripheral vestibular lesions,while a prolonged Tc may m be linked to central processing defects.Although the importance of peak gain is slightly less than that of Tc,it can provide supplementary verification for Tc.Tc can be converted with the phase of sinusoidal harmonic acceleration test,allowing these two tests to complement each other in a clinical setting.In practical applications,Tc can be influenced by factors such as the order of examination,rotation chair speed,head position,adaptability and alertness,alcohol effect,and visual conditions.Currently,the use of VST in vestibular research is mainly focused on describing its performance in caloric tests and motion sickness.Further research is needed to explore its potential applications in other areas.