下颌气囊压力反馈装置应用于前庭诱发肌源性电位检测

Vestibular Evoked Myogenic Potentials(VEMP): Clinical Setting and Reproducibility

目的介绍一种监测和控制胸锁乳突肌收缩力度的下颌气囊压力反馈装置,以提高前庭诱发肌源性电位(vestibular evoked myogenic potential,VEMP)检测结果的可重复性和可靠性。方法研究对象为19名健康志愿者,12名男性,平均年龄34.0±7.7岁;7名女性,平均年龄29.8±2.9岁;对受试者进行VEMP检测,测试时应用下颌气囊压力反馈装置。受检者取坐位,将下颌置于连接压力计的气囊上,以颈部肌肉牵引下颌压迫气囊,维持压力在120mmHg。记录胸锁乳突肌电位P13和N23反应时间、P13-N23峰值差。对其中9名志愿者连续三周每周检测一次,以检验其可重复性。结果 19例受试者P13和N23反应时间分别为13.97±1.33和24.03±1.79ms,P13-N23峰值差平均为66.89±44.1μV。左右耳之间各项指标差异均无统计学意义。9例重复检测者的结果具有良好的可重复性,P13和N23反应时间组内相关系数分别为0.8和0.93,P13-N23峰值差组内相关系数为0.97。结论行VEMP检测时应用下颌气囊压力反馈装置简单易行,受检者在检测过程中可以维持胸锁乳突肌收缩力度,提高检测结果的可重复性和可靠性。

Objective Vestibular evoked myogenic potentials （VEMP） is an objective assessment to vestibu lar function. However, the bias of the results limited its clinical application. The present study employed a novel technique to monitor and control the sternocleidomastoid muscle contraction level during VEMP measurement, which might improve the reproducibility and reliability. Methods A prospective study to measure the normal VEMP response in 19 normal hearing subjects （12 male with mean age of 34.0±7.7 years old,7 femal with mean age of 29.8± 2.9 years old）. Subjects were instructed to position the chin on the rubber bulb and using the neck flexors to maintain a pressure of 120 mmHg during the measurement. The P13 latencies, N23 latencies, and P13--N23 amplitudes were recorded. In nine subjects, the reproducibility of the technique was tested weekly in three consecutive weeks. Results The average latency of P13 was 13.97± 1.33 ms, and the latency of N23 was 24.03± 1.79 ms. The average amplitude was 66.89--44.1 uV. There was no significant difference between right and left ears in P13 latencies, N23 latencies and P13--N23 amplitudes. In nine subjects, the average measured interclass correlation coefficient （ICC） were 0.97 in amplitude, 0. 8 in P13 latency and 0. 93 in N23 latency in three consecutive weekly measurements. Conclusion The chin--rest pressure feedback technique is easy to perform during VEMP testing. Subjects can maintain a constant level of SCM contraction and neck flexion to facilitate this response with a high degree of test--retest reliability. This technique provides a means to compare VEMP across different clinical scenarios over time.