Tolerability and Efficacy of Continuous Theta-burst Stimulation for Essential Tremor: A Randomized Study.

Continuous theta-burst stimulation (cTBS) was performed with a CCY-I Magnetic Stimulator (YIRUIDE Medical Co., Wuhan, China) with an air-cooled, figure-of-eight 70 mm coil. The site of stimulation during the TMS treatment sessions was bilateral M1 and cerebellum. Real cerebellar cTBS was delivered with the coil positioned over the cerebellar hemisphere, i.e., 3 cm laterally to and 1 cm below the inion. The cTBS protocol uses a complex pattern of stimulation consisting of three-pulse bursts at 50 Hz repeated every 200ms. A total of 600 pulses that lasts for about 40 seconds were applied which could result in a sustained reduction in corticospinal excitability that outlasted the period of stimulation by 45 min. It was delivered at an intensity corresponding to 80 % of the active motor threshold (AMT), this is the minimum stimulation intensity that evokes MEPs of approximately 200 μV in amplitude in tonically contracted muscles.