Department of Neurology, Christian-Albrechts University Kiel, Germany.
Clin Neurophysiol. 2012 May;123(5):1010-5. doi: 10.1016/j.clinph.2011.08.033. Epub 2011 Oct 6.
We investigated whether essential tremor (ET) can be altered by suppressing the corticospinal excitability in the primary motor cortex (M1) with transcranial magnetic stimulation.
10 Patients with ET and 10 healthy controls underwent transcranial continuous theta-burst stimulation (cTBS) of the left primary motor hand area at 80% (real cTBS) and 30% (control cTBS) of active motor threshold in two separate sessions at least one week apart. Postural tremor was rated clinically and measured accelerometrically before and after cTBS. Corticospinal excitability was assessed by recording the motor evoked potentials (MEP) from the first dorsal interosseous muscle.
Real cTBS but not control cTBS reduced the tremor total power assessed with accelerometry. This beneficial effect was subclinical as there were no significant changes in clinical tremor rating after real cTBS. Relative to control cTBS, real cTBS reduced corticospinal excitability in the stimulated primary motor cortex only in healthy controls but not in ET patients.
Real cTBS has a beneficial effect on ET. Since cTBS did not induce a parallel reduction in corticospinal excitability, this effect was not mediated by a suppression of the corticospinal motor output.
"Inhibitory" cTBS of M1 leads to a consistent but subclinical reduction in tremor amplitude.
我们研究了经颅磁刺激抑制初级运动皮层（M1）皮质脊髓兴奋性是否可以改变原发性震颤（ET）。
10 例 ET 患者和 10 例健康对照者在至少相隔一周的两个单独疗程中，分别以 80%（真实 cTBS）和 30%（对照 cTBS）的主动运动阈接受左初级运动手区的经颅连续 theta 爆发刺激（cTBS）。在 cTBS 前后，通过临床评定和加速度计测量姿势性震颤进行临床评定，并通过记录第一背侧骨间肌的运动诱发电位（MEP）评估皮质脊髓兴奋性。
只有真实 cTBS，而不是对照 cTBS，降低了加速度计评估的震颤总功率。由于真实 cTBS 后临床震颤评分没有明显变化，这种有益的效果是亚临床的。与对照 cTBS 相比，只有在健康对照组中，而不是在 ET 患者中，真实 cTBS 降低了刺激初级运动皮层的皮质脊髓兴奋性。
真实 cTBS 对 ET 有有益的效果。由于 cTBS 没有引起皮质脊髓兴奋性的平行降低，因此这种效果不是通过抑制皮质脊髓运动输出介导的。
M1 的“抑制性”cTBS 导致振幅一致但亚临床的震颤减少。
