Objectives: To improve the diagnosis of damaged spinal motor pathways in incomplete spinal cord injury (iSCI) by assessing the facilitation of lower limbs motor evoked potentials (MEP). Methods: Control subjects (n = ...Objectives: To improve the diagnosis of damaged spinal motor pathways in incomplete spinal cord injury (iSCI) by assessing the facilitation of lower limbs motor evoked potentials (MEP). Methods: Control subjects (n = 12) and iSCI patients (n = 21) performed static and dynamic isometric foot dorsiflexions. MEPs induced by transcranial magnetic stimulation and EMG background of tibialis anterior muscle (TA) were analyzed. Static and dynamic muscle activation was performed at comparable levels of maximal voluntary contraction (MVC). The influence of the motor tasks on the excitability and facilitation of MEPs was compared between controls and iSCI patients. Results: In the controls an increased facilitation of TA MEP at lower levels of dynamic compared with static activation (10-20 % MVC) could be shown. At matched EMG background level the MEP responses were significantly increased. In the iSCI patients at a comparable level of TA activation the MEP responses were significantly reduced and 3 different patterns of MEP responses could be distinguished: i) preserved increment of TA MEP in the dynamic motor task, ii) unchanged MEP size in the dynamic and static motor task, and iii) elicitable MEPs in the dynamic motor task, which were abolished in the static motor task. Conclusions: Static and dynamic motor tasks have different effects on TA MEP facilitation. The task-dependent modulation of TA MEPs is comparable to that described for upper limb muscles. Complementary to the MEP delay this approach allows for an estimation of the severity of spinal tract damage. The task-dependent modulation of TA MEPs is an additional diagnostic tool to improve the assessment and monitoring of motor function in iSCI.展开更多
三重（冲）刺激技术（triple stimulation technique，TST）衍生于经颅磁刺激技术（transcranial magnetic stimulation，TMS），利用对冲技术将TMS诱发的脊髓运动神经元放电同步化，可定量化评估运动传导通路损伤程度，作为一种无创无...三重（冲）刺激技术（triple stimulation technique，TST）衍生于经颅磁刺激技术（transcranial magnetic stimulation，TMS），利用对冲技术将TMS诱发的脊髓运动神经元放电同步化，可定量化评估运动传导通路损伤程度，作为一种无创无痛检查技术在神经系统疾病诊断中应用广泛。展开更多
经颅磁刺激（transcranial magnetic stimulation,TMS）是利用时变磁场诱发出感应电场,即快速电流脉冲通过刺激线圈,产生瞬间磁场在脑组织里诱导产生平行于线圈的电流,进而对相关区域发挥影响作用。该技术已广泛应用于成人脑卒中、帕金...经颅磁刺激（transcranial magnetic stimulation,TMS）是利用时变磁场诱发出感应电场,即快速电流脉冲通过刺激线圈,产生瞬间磁场在脑组织里诱导产生平行于线圈的电流,进而对相关区域发挥影响作用。该技术已广泛应用于成人脑卒中、帕金森病和抑郁症等疾病。展开更多
文摘Objectives: To improve the diagnosis of damaged spinal motor pathways in incomplete spinal cord injury (iSCI) by assessing the facilitation of lower limbs motor evoked potentials (MEP). Methods: Control subjects (n = 12) and iSCI patients (n = 21) performed static and dynamic isometric foot dorsiflexions. MEPs induced by transcranial magnetic stimulation and EMG background of tibialis anterior muscle (TA) were analyzed. Static and dynamic muscle activation was performed at comparable levels of maximal voluntary contraction (MVC). The influence of the motor tasks on the excitability and facilitation of MEPs was compared between controls and iSCI patients. Results: In the controls an increased facilitation of TA MEP at lower levels of dynamic compared with static activation (10-20 % MVC) could be shown. At matched EMG background level the MEP responses were significantly increased. In the iSCI patients at a comparable level of TA activation the MEP responses were significantly reduced and 3 different patterns of MEP responses could be distinguished: i) preserved increment of TA MEP in the dynamic motor task, ii) unchanged MEP size in the dynamic and static motor task, and iii) elicitable MEPs in the dynamic motor task, which were abolished in the static motor task. Conclusions: Static and dynamic motor tasks have different effects on TA MEP facilitation. The task-dependent modulation of TA MEPs is comparable to that described for upper limb muscles. Complementary to the MEP delay this approach allows for an estimation of the severity of spinal tract damage. The task-dependent modulation of TA MEPs is an additional diagnostic tool to improve the assessment and monitoring of motor function in iSCI.
文摘三重（冲）刺激技术（triple stimulation technique，TST）衍生于经颅磁刺激技术（transcranial magnetic stimulation，TMS），利用对冲技术将TMS诱发的脊髓运动神经元放电同步化，可定量化评估运动传导通路损伤程度，作为一种无创无痛检查技术在神经系统疾病诊断中应用广泛。
