磁刺激运动诱发电位诊断颈髓髓内和髓外病变

目的 探索磁刺激运动诱发电位（ＭＦＰ）在颈髓髓内和髓外病变中的诊断价值。方法 采用磁刺激ＭＥＰ和电刺激Ｆ波相结合的方法，测定颈髓病变患者４５例，健康对照组２０例。通过记录双侧上肢外展拇短肌（ＡＰＢ）和下肢胫前肌（ＡＴ）的混合肌动作电位，计算中枢运动传导时间（ＣＭＣＴ），并与临床表现和影像学表现作对比。结果 ＡＴ肌ＭＥＰ检查结果对髓外病变较敏感，ＣＭＣＴ异常与颈髓压迫影像和上运动神经元受素表现相关。

Magnetic stimulation induced motor evoked potentials in diagnosis of cervical intramedullary and extrmnedullary disorders

Objective To investigate the diagnostic value of magnetic stimulation Motor Evoked Potentials(MEP)in cervical spinal cord lesions was investigated in this prospective clinical study.Methods Forty-five patients with cervical spinal lesions,including cervical spondylosis (n=23),cervical spinal canal stenosis (n=6),cervical spinal and cord tumors (n=10) and syringomyelitis (n=6), and 20 normal controls person were also examined by transcranial magnetic stimulation.The central motor conduction time (CMCT) was calculated after compound muscle action potentials were recorded from the abductor pollicis brevis(APB) muscles and anterior tibia (AT) muscles bilaterally,together with F test from the same extremities.Correlations of abnormal CMCT with radiologically proved spinal cord compression and with clinical signs of upper motor neuron involvement were tested.Results Aomng 34 patients with extramedullary lesions, abnorma lCMCT to the APB was in 22 kevealed(64 7%)and to the AT in 24(70 6%).In 11 Patients with intramedullaty lesions,abnormal CMCT to the APB was revealed observed in 3 (27 3%)and to the AT in 3(27 3%).The sensitivity of CMCT to the AT in extramedullary disorders was significantly higher.Abnormal CMCT also highly correlated with spinal cord compression and with upper motor neuron involvement.Subclinical lesions were detected by an abnormal CMCT in 5 patients(11 1%).Conclusions In extramedullary lesions,measurement of CMCT to the AT is more sensitive.Abnormal CMCT correlates with spinal cord compression and clinical signs of upper motor neuron involvement,MEP has high diagnostic value in cervical cord lesions,which even can detect subclinical lesions.