脑干听觉诱发电位对前庭系统性眩晕的诊断价值

Diagnostic Value of Brainstem Auditory Evoked Potential in Patients with Vestibular System Vertigo

目的：探讨脑干听觉诱发电位（BAEP）对前庭周围性眩晕和中枢性眩晕的鉴别诊断价值。方法：对96例前庭系统性眩晕患者（研究组）及50名（100只耳）健康人（对照组）进行BAEP检查，观察两组Ⅰ、Ⅲ、Ⅴ波的潜伏期（PL）、波形分化情况，Ⅰ-Ⅲ、Ⅲ-Ⅴ、Ⅰ-Ⅴ波的峰间潜伏期（IPL）、两耳侧间差（ILD）以及Ⅴ／Ⅰ波幅比值。对照组50名均为与研究组年龄、性别相匹配的健康人。结果：对照组Ⅰ、Ⅲ、Ⅴ波波形分化良好、重现性佳，各波PL及IPL均正常，Ⅱ一Ⅴ IPL〈Ⅰ～Ⅲ IPL，同侧Ⅴ／Ⅰ波幅比值大于0．5，各波PL侧差（ILD）〈0.4ms研究组96例中有68例（71％）异常。两组的PL和IPL数值进行比较存在着显著性差异（P〈0．01）。研究组68例BAEP异常者，依其表现分为两型。①内耳型28例，表现为Ⅰ波分化不良或波形消失，PL延长及其后各波相应延长，Ⅰ—ILD大于0.4ms；②脑干型40例，表现为Ⅰ波正常，Ⅲ波或Ⅴ波PL延长或波形消失，Ⅲ-Ⅴ、Ⅰ—Ⅴ的IPL延长，Ⅴ／Ⅰ波幅比小于0．5及双侧Ⅴ—ILD〉0．4ms，两型之间的Ⅰ、Ⅲ、Ⅴ波PL及Ⅲ-Ⅴ、Ⅰ—Ⅴ的IPL存在着显著性差异（P〈0．01），而Ⅰ-Ⅲ的IPL无显著性差异（P〉0．05）。结论：BAEP是鉴别前庭系统周围性和中枢性眩晕比较敏感的诊断方法。

Objective：To explore the differential diagnostic value of brainstem auditory evoked potential （BAEP） in patients with vestibular system peripheral or central vertigo. Methods： The BAEPs of 96 patients with vestibular vertigo and 50 health volunteers （100 ears）, which used as control group, they were age- and sex - matched with those of experimental group, were detected. Meanwhile; the Peak Latency （PL） and change of waveform I. Ⅲ. Ⅴ, the interpeak latency（IPL） of waveform Ⅰ - Ⅲ, Ⅲ Ⅴ arid I - Ⅴ, the inter- ears latency difference （ILD）and amphtude ratio of wave Ⅴ/Ⅰ were observed and analyzed. Results： The BAEPs of control group showed： ①fine differentiation and good reproducibility of waveform Ⅰ . Ⅲ. Ⅴ ;②normal PL and IPL ③the IPL of wave Ⅲ - Ⅴ was less than those of Ⅰ - Ⅲ ;④the homolateral amplitude ratio of Ⅴ ： Ⅰ exceed 0.5;⑤the ILD of various wave PL less than 0.4 milliseconds. However, in patients group, 68 BAEP were abnormal, the abnormality rate was 71% （68/96）. Two abnormal types were classified by their characteristics, as follow： ①inner - ear type（28 cases） ： showing undifferentiating or disappearance of wave Ⅰ, prolongation of PL in wave Ⅰ and accordingly extended ILD of all later waves, the ILD of waveform Ⅰ exceeded 0.4 milliseconds; ②Brain - stem type（40 cases） ： showing normal wave Ⅰ, prolonged PL or waveform disappearance of waves Ⅲ or Ⅴ .The IPL of waves Ⅲ - Ⅴ and Ⅰ- Ⅲ were prolonged,and amphtude ratio of Ⅴ/Ⅰ was less than 0.5,and I LD of bilateral wave Ⅴ was more than 0.4 millisconds. The PL of wave Ⅰ. Ⅲ . Ⅴ, IPL of Ⅲ - Ⅴ. Ⅰ - Ⅴ, homolateral IPL of wave Ⅰ and Ⅴ, present significant difference between two types, oppositely, the IPL of Ⅰ- Ⅲ was not significant difference. Condusion： BAEP detection might be a more sensitive approach for differentiating vestibular system peripheral and central vertigo.