Circadian Adaptive DBS in Essential Tremor

This single-center study will investigate the feasibility of developing an adaptive Deep brain stimulation (aDBS) strategy using thalamic circadian rhythm as a control signal. It will evaluate the safety and tolerability of aDBS compared to conventional DBS (cDBS) in a double-blinded cross-over design.

This study will recruit 25 Essential Tremor (ET) patients implanted with the bidirectional neural interface, Medtronic Percept PC (FDA approved), attached to DBS directional lead(s) (Sensight) implanted unilaterally or bilaterally in the ventral intermediate nucleus (VIM) and who are receiving adequate control of their tremor with VIM DBS.

First, the brain signal will be recorded for 1 month to identify circadian fluctuations that may be used to identify the period of sleep. Second, for each patient, an aDBS algorithm based on individualized brain activity will be developed and tested for 2 weeks in a double-blinded cross-over design comparing aDBS and cDBS. Third, at the end of this 4-week trial, patients who preferred aDBS will have the opportunity to stay on aDBS for 6 months, allowing to assess the long-term tolerability of the aDBS.

Each patient enrolled in this study will participate in 7 study visits over 8 months during which chronic brain recordings and aDBS will be set up. Symptoms and stimulation-induced side effects will be assessed by clinicians during these visits. Self-rating scales and wearable will be provided to track tremor, sleep, and movement at home.

• Patient's quality of life as assessed by the Quality of Life in Essential Tremor Questionnaire (QUEST), adapted for a 2-week assessment [Срок оценки: From enrollment to the end of study (8 months)]
• The Tremor Research Group Essential Tremor Rating Scale (TETRAS) Activities of Daily Living Subscale [Срок оценки: From enrollment to the end of study (8 months)]
• Sleep quality as assessed by the Pittsburgh Sleep Quality Index (PSQI), adapted for a 2-week assessment [Срок оценки: From enrollment to the end of study (8 months)]
• Patient's cognition as assessed by the Montreal Cognitive Assessment 5-Minute Protocol (Mini MoCA) [Срок оценки: From enrollment to the end of study (8 months)]
• Patient's mood as assessed by the Beck Depression Inventory-II (BDI-II), adapted for a 2-week assessment [Срок оценки: From enrollment to the end of study (8 months)]
• Patient's impression as assessed by the Patient Global Impression of Change Scale (PGI-C) [Срок оценки: From enrollment to the end of study (8 months)]
• Patient's self-report of side effects, tremor severity, and sleep [Срок оценки: From enrollment to the end of study (8 months)]
• Presence/severity of tremor tracked with wearable device [Срок оценки: From enrollment to the end of double-blind crossover period (first two months of study)]
• Battery drainage/Stimulation energy use as assessed by Total Electrical Energy Delivered (TEED) [Срок оценки: From enrollment to the end of study (8 months)]