Badawy Radwa, Macdonell Richard, Jackson Graeme, Berkovic Samuel
Department of Neurology, Austin Health, Studley Road, Heidelberg, 3084 Victoria, Australia.
Brain. 2009 Apr;132(Pt 4):1013-21. doi: 10.1093/brain/awp017. Epub 2009 Feb 27.
In this study, transcranial magnetic stimulation was used to investigate motor cortical excitability changes in the peri-ictal period, in drug-naive new-onset epilepsy patients. Eighty-seven studies were performed on 58 patients (23 with idiopathic generalized epilepsy and 35 with focal epilepsy) within 72 h before or after a seizure. Fifty studies in 35 patients were within 24 h of a seizure. In all 58 patients, an interictal baseline study was performed, at least 14 days from a seizure. Motor threshold and paired pulse recovery curve results obtained at short (2-15 ms) and long (50-400 ms) interstimulus intervals in each hemisphere (at <24 h pre- or post-seizure and 24-72 h pre- and post-seizure) were compared against the interictal results and normal control values obtained from 32 subjects. The nature of the seizure (generalized, focal or focal with secondary generalization) was also recorded. Increased motor cortex excitability, measured by decreased motor threshold, increased intracortical facilitation and decreased intracortical inhibition at short and long interstimulus intervals was seen in the 24 h before a seizure. Conversely, decreased excitability occurred in the 24 h after a seizure. These effects were bilateral in tonic-clonic seizures in idiopathic generalized epilepsy and also in secondarily generalized seizures in patients with focal epilepsy. Similar changes were seen in the hemisphere ipsilateral to the seizure focus in focal seizures that did not secondarily generalize, accompanied by complex excitability changes in the contralateral hemisphere. These effects were not apparent in the 24-72 h window. These results show that there are major and prolonged changes in motor cortex excitability in the pre and the postictal 24 h. Increased excitation precedes the seizure by hours and there is a similar period of decreased excitability following a seizure.
在本研究中，经颅磁刺激被用于调查初发未用药的癫痫患者发作期周围运动皮质兴奋性的变化。对58例患者（23例特发性全身性癫痫患者和35例局灶性癫痫患者）在发作前或发作后72小时内进行了87项研究。35例患者中的50项研究是在发作后24小时内进行的。对所有58例患者，在距上次发作至少14天进行了发作间期基线研究。将每个半球在短（2 - 15毫秒）和长（50 - 400毫秒）刺激间隔时（发作前或发作后<24小时以及发作前和发作后24 - 72小时）获得的运动阈值和配对脉冲恢复曲线结果，与发作间期结果以及从32名受试者获得的正常对照值进行比较。还记录了发作的性质（全身性、局灶性或继发全身性的局灶性发作）。在发作前24小时，可见运动皮质兴奋性增加，表现为运动阈值降低、皮质内易化增加以及在短和长刺激间隔时皮质内抑制降低。相反，发作后24小时兴奋性降低。这些效应在特发性全身性癫痫的强直阵挛发作中以及局灶性癫痫患者的继发全身性发作中是双侧性的。在未继发全身性发作的局灶性发作中，在发作灶同侧半球可见类似变化，同时对侧半球伴有复杂的兴奋性变化。在24 - 72小时时间段内这些效应不明显。这些结果表明，在发作前和发作后的24小时内运动皮质兴奋性有重大且持续的变化。发作前数小时兴奋性增加，发作后有类似的兴奋性降低期。
