中文摘要：

目的研究肌电图(electromyogram,EMG)修正对前庭诱发肌源性电位（Vestibular-evokedmyogenic potentials,VEMPs）结果产生的影响，并建立修正后的cervical Vestibular-evoked myogenic potential（cVEMP）及ocular Vestibular Evoked Myogenic Potential（oVEMP）正常值范围，为临床上准确评估前庭感受器功能提供更可靠的参考依据。方法采用500Hztone-burst刺激声对20名（40耳）听力正常且无耳蜗及前庭系统疾病的正常青年人进行cVEMP及oVEMP测试。受试者年龄为20-30岁，平均年龄（23.76±2.81）岁。测试强度为100dBnHL，通过ER-3A标准插入式耳机给声，测试时体位采取坐姿。结果所有受试者均能引出清晰可重复的cVEMP及oVEMP波形。Tone-burstc VEMP的P1潜伏期为14.13±1.97（ms），N1潜伏期为21.54±2.23（ms），幅值为1.63±0.60（μV）。Tone-burstoVEMP的N1潜伏期为10.15±0.72（ms），P1潜伏期为15.79±1.01（ms），幅值为1.38±1.02（μV）。cVEMP修正前后的振幅有显著性差异（*P<0.05），修正前后比值达到40~50倍。结论EMG修正对振幅标准化有重要意义，其中对cVEMP的测试结果影响较大，建立一组EMG修正后VEMPs的正常参考值范围能够更准确评估双侧不对称性。Tone-burstcVEMP及oVEMP引出率高，可作为临床上评估椭圆囊和球囊功能的常规检测方法。

英文摘要：

Objective To study the influence of EMG rectification on cervical and ocular vestibular evoked myogenicpotentials,and to establish the normal range of cervical vestibular evoked myogenic potentials(cVEMP)and ocularvestibular evoked myogenic potentials(oVEMP)for accurate assessment of vestibular receptor function.MethodsTwenty normal hearing adult volunteers(10male and10female,40ears)without ear diseases,aged from20to30years(mean age=23.76±2.81years),were included in the study.cVEMPs and oVEMPs were induced using500Hztone-bursts,delivered through ER-3A standard insert earphones at100dB nHL,while the subject assumed a sitting position.Results cVEMP and oVEMP responses with clear and repeatable waveforms were acquired in all subjects.The P1and N1latencies of cVEMPs were14.13±1.97and21.54±2.23ms,respectively,with an amplitude of1.63±0.60μV.oVEMP P1and N1latencies were10.15±0.72ms and15.79±1.01ms,respectively,with an amplitude of1.38±1.02μV.EMG rectification of cVEMPs yielded amplitude differences of40-50times(P<0.05).Conclusions EMG rectificationhas a significant effect on amplitude normalization,especially for cVEMPs.Establishment of normal VEMP amplituderange with EMG rectification can improved the accuracy in the assessment of response asymmetry.The high responserate of tone-burst evoked VEMPs in a sitting position makes this test a valuable tool in vestibular evaluation,not onlyfor assessment of utricular and saccular functions,but also for differential diagnosis.