title: Placebo-controlled study of rTMS for the treatment of Parkinson's disease.
abstract: The objective of this study is to assess the safety and efficacy of repetitive transcranial magnetic stimulation (rTMS) for gait and bradykinesia in patients with Parkinson's disease (PD). In a double-blind placebo-controlled study, we evaluated the effects of 25 Hz rTMS in 18 PD patients. Eight rTMS sessions were performed over a 4-week period. Four cortical targets (left and right motor and dorsolateral prefrontal cortex) were stimulated in each session, with 300 pulses each, 100% of motor threshold intensity. Left motor cortex (MC) excitability was assessed using motor evoked potentials (MEPs) from the abductor pollicis brevis. During the 4 weeks, times for executing walking and complex hand movements tests gradually decreased. The therapeutic rTMS effect lasted for at least 1 month after treatment ended. Right-hand bradykinesia improvement correlated with increased MEP amplitude evoked by left MC rTMS after individual sessions, but improvement overall did not correlate with MC excitability. rTMS sessions appear to have a cumulative benefit for improving gait, as well as reducing upper limb bradykinesia in PD patients. Although short-term benefit may be due to MC excitability enhancement, the mechanism of cumulative benefit must have another explanation.
authors.affiliation: Human Motor Control Section, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, Maryland 20892-1428, USA. lomarev@ninds.nih.gov
authors.forename: Mikhail P
authors.initials: MP
authors.lastname: Lomarev
authors.forename: Sulada
authors.initials: S
authors.lastname: Kanchana
authors.forename: William
authors.initials: W
authors.lastname: Bara-Jimenez
authors.forename: Meena
authors.initials: M
authors.lastname: Iyer
authors.forename: Eric M
authors.initials: EM
authors.lastname: Wassermann
authors.forename: Mark
authors.initials: M
authors.lastname: Hallett
mesh_terms: D019054:Evoked Potentials, Motor / Q000502:physiology; D005260:Female; D006225:Hand / Q000503:physiopathology; D006801:Humans; D018476:Hypokinesia / Q000503:physiopathology / Q000628:therapy; D008297:Male; D008875:Middle Aged; D009044:Motor Cortex / Q000503:physiopathology; D010300:Parkinson Disease / Q000175:diagnosis / Q000503:physiopathology / Q000628:therapy*; D017397:Prefrontal Cortex / Q000503:physiopathology; D012720:Severity of Illness Index; D050781:Transcranial Magnetic Stimulation / Q000295:instrumentation*; D016138:Walking