A model predicting optimal parameters for deep brain stimulation in essential tremor.
In nine patients with essential tremor (14 thalami), the authors varied frequency, voltage, and pulsewidth of thalamic deep brain stimulation, and quantified postural tremor. Low frequency stimulation aggravated tremor; the effect increased with increasing voltage. High frequency stimulation had a U-shaped relation to voltage, with minimum tremor at an optimal voltage characteristic of the individual thalamus and increases in voltage beyond the optimum reduced tremor suppression.Based on the hypothesis that tremor response to deep brain stimulation resulted from two competing processes, the authors successfully modeled the relationship of tremor to voltage and frequency of stimulation using a mathematical model. The optimum voltage predicted by the model agreed with the empirically measured value. Moreover, the model made accurate predictions at high stimulation frequency based on measurements made at low stimulation frequency.Our results indicate there is an optimal voltage for tremor suppression by thalamic deep brain stimulation in most patients with essential tremor. The optimum varies across patients, and this is related to electrode position. A mathematical model based on "competing processes" successfully predicts optimum voltage in individual patients. This supports a competing processes model of deep brain stimulation effects.
Cooper
Scott E
SE
Department of Neurology, Center for Neurological Restoration Cleveland Clinic Foundation, Cleveland, Ohio, USA. coopers2@ccf.org
Kuncel
Alexis M
AM
Wolgamuth
Barbara R
BR
Rezai
Ali R
AR
Grill
Warren M
WM
D000328:Adult; D000368:Aged; D046690:Deep Brain Stimulation / Q000379:methods*; D020329:Essential Tremor / Q000628:therapy*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D008959:Models, Neurological; D008962:Models, Theoretical
Mov Disord. 2002;17 Suppl 3:S63-8
11948756
Mov Disord. 2004 Oct;19(10):1163-8
15390071
Neurology. 2003 Mar 11;60(5):786-90
12629234
Acta Neurol Belg. 2005 Sep;105(3):149-57
16255153
Mov Disord. 2006 Nov;21(11):1920-8
16972236
J Neurophysiol. 2004 Apr;91(4):1457-69
14668299
J Neurosurg. 1979 Mar;50(3):290-7
370349
Mov Disord. 2000 Sep;15(5):919-24
11009200
Neuroreport. 2004 May 19;15(7):1137-40
15129161