Stimulation of the motor cortex for disabling essential tremor.
OBJECTIVE
To examine the safety and efficacy of targeted stimulation of the motor cortex as a treatment for essential tremor (ET).


METHODS
At the University of Kansas Medical Center, two patients with essential tremor received stimulation of the (contralateral) motor cortex using an investigational implantable pulse generator (IPG). Patients were evaluated with the Fahn Tolosa Marin tremor rating scale (TRS) at baseline, 1 week and 4 weeks after surgery, both with stimulation turned on and turned off. Both patients also received neuropsychological assessments at baseline and again after surgery.


RESULTS
Patient 1 was a 75-year-old male with tremor for 20 years. His baseline total TRS score was 61 and his TRS 1 month after surgery was 57. His IPG was set at 30 Hz, 3 mA and 250 micros pulse width. Patient 2 was a 60-year-old male with tremor for over 10 years. His baseline total TRS was 47 and it was 43, 1 month after surgery. His IPG was set at 50 Hz, 5 mA and 250 micros pulse width. There were no adverse effects.


CONCLUSIONS
Cortical stimulation of the primary hand motor cortex contralateral to the dominant hand was ineffective for the treatment of ET with the stimulation parameters used in this study. Future research examining other stimulation parameters is necessary to determine if there is a role for cortical stimulation in the treatment of ET.
Lyons
Kelly E
KE
Department of Neurology, University of Kansas Medical Center, 3599 Rainbow Blvd, Mailstop 2012, Kansas City, KS 66160, USA. lyons.kelly@att.net
Wilkinson
Steven B
SB
Pahwa
Rajesh
R
D000368:Aged; D002540:Cerebral Cortex; D046690:Deep Brain Stimulation / Q000379:methods*; D004567:Electrodes, Implanted; D020329:Essential Tremor / Q000503:physiopathology / Q000523:psychology / Q000628:therapy*; D006801:Humans; D008297:Male; D008875:Middle Aged; D009483:Neuropsychological Tests; D010865:Pilot Projects; D017211:Treatment Failure