title: Neurophysiologic correlates of sonication treatment in patients with essential tremor.
abstract: Transcranial magnetic resonance imaging-guided high-intensity focused ultrasound (MRgHIFU) is gaining attention as a potent substitute for surgical intervention in the treatment of neurologic disorders. To discern the neurophysiologic correlates of its therapeutic effects, we applied MRgHIFU to an intractable neurologic disorder, essential tremor, while measuring magnetoencephalogram mu rhythms from the motor cortex. Focused ultrasound sonication destroyed tissues by focusing a high-energy beam on the ventralis intermedius nucleus of the thalamus. The post-treatment effectiveness was also evaluated using the clinical rating scale for tremors. Thalamic MRgHIFU had substantial therapeutic effects on patients, based on MRgHIFU-mediated improvements in movement control and significant changes in brain mu rhythms. Ultrasonic thalamotomy may reduce hyper-excitable activity in the motor cortex, resulting in normalized behavioral activity after sonication treatment. Thus, non-invasive and spatially accurate MRgHIFU technology can serve as a potent therapeutic tool with broad clinical applications.
authors.affiliation: Department of Neurosurgery, Yonsei University College of Medicine, Seoul, Korea.
authors.forename: Jin Woo
authors.initials: JW
authors.lastname: Chang
authors.affiliation: Department of Brain and Cognitive Engineering, Korea University, Seoul, Korea. Electronic address: min_bk@korea.ac.kr.
authors.forename: Byoung-Kyong
authors.initials: BK
authors.lastname: Min
authors.affiliation: Department of Neurosurgery, Yonsei University College of Medicine, Seoul, Korea.
authors.forename: Bong-Soo
authors.initials: BS
authors.lastname: Kim
authors.affiliation: Department of Neurosurgery, Yonsei University College of Medicine, Seoul, Korea.
authors.forename: Won Seok
authors.initials: WS
authors.lastname: Chang
authors.affiliation: Korea Research Institute of Standards and Science, Daejeon, Korea.
authors.forename: Yong-Ho
authors.initials: YH
authors.lastname: Lee
mesh_terms: D000368:Aged; D058256:Brain Waves; D020329:Essential Tremor / Q000175:diagnosis* / Q000503:physiopathology / Q000601:surgery*; D005240:Feasibility Studies; D057086:High-Intensity Focused Ultrasound Ablation / Q000379:methods*; D006801:Humans; D064795:Intraoperative Neurophysiological Monitoring / Q000379:methods*; D053783:Magnetic Resonance Imaging, Interventional / Q000379:methods*; D015225:Magnetoencephalography; D008297:Male; D008875:Middle Aged; D016896:Treatment Outcome
keywords: Essential tremor; Magnetic resonance imaging-guided high-intensity focused ultrasound; Magnetoencephalography; Mu rhythm; Thalamus