Long-term deep brain stimulation in a patient with essential tremor: clinical response and postmortem correlation with stimulator termination sites in ventral thalamus - Case report

Essential tremor can be suppressed with chronic, bilateral deep brain stimu lation (DBS) of the ventralis intermedius nucleus (Vim), the cerebellar rec eiving area of the motor thalamus. The goal in this study was to correlate the location of the electrodes with the clinical efficacy of DBS in a patie nt with essential tremor. The authors report on a woman with essential trem or in whom chronic bilateral DBS directed to the ventral thalamus produced adequate tremor suppression until her death from unrelated causes 16 months after placement of the electrodes. Neuropathological postmortem studies of the brain in this patient demonstrated that both stimulators terminated in the Vim region of the thalamus, and that chronic DBS elicited minor reacti ve changes confined to the immediate vicinity of the electrode tracks. Alth ough the authors could not identify neuropathological abnormalities specifi c to essential tremor, they believe that suppression of essential tremor by chronic DBS correlates with bilateral termination of the stimulators in th e Vim region of the thalamus.