多发性硬化患者前庭诱发肌源性电位的临床意义

Clinical significance of vestibular evoked myogenic potentials in multiple sclerosis patients

目的研究多发性硬化(multiple sclerosis,MS)患者前庭诱发肌源性电位(vestibularevoked myogenic potentials,VEMPs)各参量的变化及临床意义,比较VEMPs与核磁共振、脑干听觉诱发电位对MS病变的检测能力。方法采用双耳短声刺激记录37例MS患者(有脑干症状21例、无脑干症状16例)和20名健康对照的VEMPs的潜伏期和振幅值,计算双侧在13ms左右出现的正波(p13)波幅潜伏期差值(Δp13)和振幅比(SR)。37例MS患者均做核磁共振成像,其中33例记录脑干听觉诱发电位。结果有脑干症状组和对照组相比,p13潜伏期显著延长[左侧为(13.84±2.57)ms和(12.20±1.10)ms,P<0.05;右侧为(14.69±2.96)ms和(12.10±2.60)ms,P<0.01],Δp13显著增大(1.63±1.82和1.00±1.44,P<0.01),而无脑干症状组差异无统计学意义。两组MS患者的p13-n23(在23ms左右出现的负波)振幅值与对照组相比均降低[左侧分别为(149.98±52.2)、(175.51±49.22)、(272.80±165.81)μV;右侧分别为(156.88±97.04)、(167.74±57.32)、(257.50±138.49)μV,P均<0.05],扩展的残疾功能量表评分与振幅有相关性(左侧r=0.45,右侧r=0.46,P均<0.05)。VEMPs与核磁共振相比,对病灶的检出率低(分别为33%与100%,P<0.05),与脑干听觉诱发电位相比差异无统计学意义。结论p13潜伏期及Δp13可作为判定MS前庭脊髓通路脱髓鞘的参考指标。VEMPs作为辅助诊断MS的一项新的诱发电位,对脑干病灶的诊断有一定临床参考意义。

Objective To investigate the change of vestibular evoked myogenic potentials （VEMPs） in multiple sclerosis （MS） and compare it with conventional MRI and brainstem auditory evoked potentials （BAEPs） for the diagnosis of MS. Methods The latency and amplitude of 37 MS patients （21 patients with clinical brainstem involvement （BS ~ group） , 16 patients without clinical brainstem dysfunction （ BS - group） ） and 20 normal controls were recorded by binaural clicks method, and the ratio of bilateral amplitudes （SR） and p13 latency asymmetry（ Δpl3 ） were calculated. 37 of these patients underwent MRI recording, among whom 33 patients underwent BAEPs recording as well. Results The p13 latency and Δp13 of VEMPs in the BS ^＋ group was significantly different from those of the control group （p13 latency：left （13.84±2.57） vs （12.20±1.10） ms, P〈0.05; right （14.69±2.96） vs （12.10±2.60） ms,P〈 0. 01 ; Δp13 ： 1.65 ± 1.82 vs 1. 00 ± 1.44, P 〈 0.01 ）. No significant difference was found between the BS - group and the control group. The amplitudes were in correlation with expanded disability status scale （EDSS） score （ r = 0. 45 （left） , r = 0.46 （right） , P 〈 0. 05 ）. when assessing of brainstem dysfunction in BS^＋ group, MRI showed brainstem lesion in 9 patients with normal VEMPs ,while 2 patients with normal MRI had abnormal VEMPs. In BS- group, VEMPs were abnormal in 1 patients with normal Mill, while ？ cases were on the contrary. The detection ability of VEMPs was lower than that of in MRI （33% vs 100% ,P 〈 0. 05）. There was no significant difference between VEMPs and BAEPs. Conclusion The p13 latency and Δp13 of VEMPs are the most reliable index, and VEMPs may be applicable in clinic as a valuable tool in the detection of demyelinating lesions in the vestibulo-spinal pathway of MS.