title: Effect of stimulation frequency on tremor suppression in essential tremor.
abstract: We sought to determine the effect of deep brain stimulation (DBS) frequency on tremor suppression in essential tremor (ET) patients with deep brain stimulators implanted in the ventral intermediate nucleus (VIM) of the thalamus. A uniaxial accelerometer was used to measure tremor in the right upper extremity of subjects with a diagnosis of ET who had DBS electrodes implanted in the left VIM. The root-mean-square acceleration was used as the index of tremor magnitude and normalized to the OFF DBS condition. There was a highly significant inverse sigmoidal relationship between stimulation frequency and normalized tremor acceleration (X(2)/DoF = 0.42, r(2) = 0.997). Tremor acceleration had a nearly linear response to stimulation frequencies between 45 and 100 Hz with little additional benefit above 100 Hz. These findings have two important implications. Clinically, frequency of thalamic stimulation is an important variable for optimal tremor control with maximal benefit achieved with 100 to 130 Hz in most patients. Second, thalamic DBS provides tremor benefit in a graded manner and is not an all-or-nothing phenomenon.
authors.affiliation: Department of Neurology, Washington University in St. Louis, St. Louis, Missouri, USA.
authors.forename: Mwiza
authors.initials: M
authors.lastname: Ushe
authors.forename: Jonathan W
authors.initials: JW
authors.lastname: Mink
authors.forename: Fredy J
authors.initials: FJ
authors.lastname: Revilla
authors.forename: Angie
authors.initials: A
authors.lastname: Wernle
authors.forename: Patricia
authors.initials: P
authors.lastname: Schneider Gibson
authors.forename: Lori
authors.initials: L
authors.lastname: McGee-Minnich
authors.forename: Minna
authors.initials: M
authors.lastname: Hong
authors.forename: Keith M
authors.initials: KM
authors.lastname: Rich
authors.forename: Kelly E
authors.initials: KE
authors.lastname: Lyons
authors.forename: Rajesh
authors.initials: R
authors.lastname: Pahwa
authors.forename: Joel S
authors.initials: JS
authors.lastname: Perlmutter
mesh_terms: D000328:Adult; D000368:Aged; D046690:Deep Brain Stimulation / Q000295:instrumentation*; D020329:Essential Tremor / Q000628:therapy*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D049268:Positron-Emission Tomography; D020651:Ventral Thalamic Nuclei / Q000098:blood supply / Q000502:physiology