Department of Neurology, Austin Health, Heidelberg, Australia.
Ann Neurol. 2010 Jan;67(1):64-73. doi: 10.1002/ana.21806.
Approximately 30% of patients with newly diagnosed epilepsy do not respond to antiepileptic drugs (AEDs), but this is not predictable. We used transcranial magnetic stimulation to determine the effect of AEDs on cortical excitability in patients with epilepsy and correlated this with a successful response to treatment.
Ninety-nine drug-naïve patients with newly diagnosed epilepsy (55 idiopathic generalized epilepsy, 44 focal epilepsy) were evaluated. Motor threshold and cortical excitability on recovery curve analysis were measured before and 4 to 16 weeks after starting medication. After 1 year of treatment, 43 of 55 idiopathic generalized epilepsy and 26 of 44 focal epilepsy patients were seizure free.
A decrease in cortical excitability occurred in the seizure-free group as indicated by an increase in motor threshold (p < 0.05) and intracortical inhibition on recovery curve analysis, maximum at the 250-millisecond interstimulus interval (p < 0.01) compared with pretreatment values. These changes were not present in the group with ongoing seizures.
Seizure freedom is marked by a reduction in transcranial magnetic stimulation measures of cortical excitability, evident shortly after beginning therapy. This virtual normalization of cortical excitability occurred regardless of the seizure characteristics or AED used. Failure to show this response to AED treatment may be valuable as an early predictor of pharmacoresistance in individual patients.
约 30%的新诊断癫痫患者对抗癫痫药物（AEDs）无反应，但这是不可预测的。我们使用经颅磁刺激来确定 AED 对癫痫患者皮质兴奋性的影响，并将其与治疗的成功反应相关联。
评估了 99 例新诊断为癫痫的药物初治患者（55 例特发性全面性癫痫，44 例局灶性癫痫）。在开始药物治疗前和 4 至 16 周后测量运动阈值和恢复曲线分析的皮质兴奋性。经过 1 年的治疗，55 例特发性全面性癫痫中的 43 例和 44 例局灶性癫痫中的 26 例无癫痫发作。
无癫痫发作组的皮质兴奋性下降，表现为运动阈值增加（p < 0.05）和恢复曲线分析的皮质内抑制增加，在 250 毫秒刺激间隔时最大（p < 0.01），与治疗前相比。在持续癫痫发作的组中没有这些变化。
无癫痫发作的特征是经颅磁刺激测量的皮质兴奋性降低，在开始治疗后不久即可观察到。这种皮质兴奋性的虚拟正常化发生在无论癫痫特征或使用何种 AED 治疗。未能显示对 AED 治疗的这种反应可能是个体患者药物抵抗的早期预测指标。
