前庭诱发肌性电位检测的最佳声刺激参数研究

目的通过比较不同的声刺激模式对前庭诱发肌性电位的影响，确定前庭诱发肌性电位检测的最佳声刺激模式。方法9名健康志愿者被随机分成三组，按3×3拉丁方析因设计，对3个不同频率（250、500、750Hz）、3个不同刺激重复率（5、7、10Hz）、3个不同平台时间（2、5、10ms）的短纯音诱发的前庭诱发肌性电位（VEMP）进行测试，每人以随机次序进行9次测试。比较前庭诱发肌性电位的诱发率、潜伏期、波间幅度及双侧幅度不对称比。结果不同短纯音频率对双侧VEMP的潜伏期及幅度及双侧幅度不对称比均有影响，按500、250、750Hz顺序，双侧P13／N23潜伏期依次增加}双侧P13／N23幅度依次减少；双侧幅度不对称比依次增加。500Hz短纯音刺激时双侧幅度最大且双侧幅度不对称比最小；5、7、10Hz3种不同刺激重复率对双侧VEMP的潜伏期、波间幅度及双侧幅度不对称比均无影响，2、5、10ms 3种短纯音不同平台持续时间对双侧VEMP的幅度有影响，按10、5、2ms顺序，双侧VEMP的幅度逐渐增加。而3种短纯音不同平台持续时间对双侧VEMP的潜伏期、双侧幅度不对称比未有明显影响。结论VEMP的最佳声刺激参数为平台时间2ms、频率500Hz、刺激重复率5Hz。

Study on optimal sound stimulation of vestibular evoked myogenic potentials

Objective We planned to determine the optimal sound stimulation configuration of vestibular evoked myogenic potentials （VEMP） by investigating the effect of different sound stimulation parameters. Methods Nine healthy male volunteers were randomly divided into three groups. According to three-by-three Latin square factorial design, each subject being performed with nine VEMP tests induced by short tune burst （STB） with three different frequencies （250, 500, 750 Hz respectively）, three different repetition rates （5, 7, 10 Hz respectively） as well as three different plateau times （2, 5, 10 ms respectively） randomly. The induction rate of VEMP response, the latency of VEMP, and the interpeak amplitude and the asymmetry ratio （AR） of bilateral interpeak amplitude of VEMP were recorded. Results Different short tune burst frequencies had signficant effects on the latencies and the amplitude as well as AR of VEMP. In sequence of 500, 250 and 750 Hz, the latencies and AR of VEMP progressively increased while the interpeak amplitude of VEMP progressively decreased. The largest amplitude sand of lowest AR of VEMP was obtained at 500 Hz. Different STB repetition rates （5,7,10 Hz） had no significant effect on the latencies and the amplitude or AR of VEMP. Different STB plateau times had a significant effect on the amplitude of VEMP. However, the latencies and the AR of VEMP were not affected by different plateau times in sequence of 2,5 and 10 ms, and the interpeak amplitude of VEMP progressively increased. Conclusions The optimal stimulation pattern for evoking STB of VEMPs is frequency 500 Hz; stimulation repetition rate 5 Hz; and plateau time 2 ms.