On demand deep brain stimulation for essential tremor: an approach to avoid tolerance?

Background: Deep Brain Stimulation (DBS) of the thalamic nucleus ventralis intermedius (VIM) is an established therapy for essential Tremor (ET), but loss of efficacy due to tolerance may occur (2). Objective: To evaluate if On Demand DBS of the VIM can avoid tolerance. Methods: Among 20 patients who obtained DBS were 3 patients with ET who in the past 2 years obtained left hemisphere DBS implants targeting the VIM. These patients were instructed to switch on DBS with a magnet only when using their right hand for motor tasks (e.g. writing, drinking, eating). DBS programming was chosen that allowed the best funct…