Neuromodulation Strategies for Treatment-Resistant Essential Tremor Using Chronos™ DBS

Neuromodulation in Treatment Resistant Essential Tremor in Early Habituation - Investigating Low and High Frequencies / Waveform Shaping / Pulse and Bursts / Combination Therapy in Deep Brain Stimulation Utilizing the Boston Scientific® Chronos™ Software

The goal of this observational study is to learn whether a new way of programming Deep Brain Stimulation (DBS) can improve and maintain tremor control in adults with essential tremor (ET) who stopped responding to standard DBS therapy.

The main questions it aims to answer are:

• 1. Can advanced DBS settings, using varied stimulation patterns, frequencies, and pulses, restore tremor control in people with ET who lost benefit from standard Ventral Intermedius Deep Brain Stimulation (VIM-DBS)?
• 2. Do these advanced settings provide more stable, longer-lasting tremor improvement over time?

Researchers will compare six different stimulation settings to see if any of them can improve tremor symptoms when standard DBS programming no longer works.

Participants will:

• Complete a clinic visit where they try six different DBS stimulation settings using specialized Chronos software.
• Be randomly assigned to one of these settings to use at home.
• Receive a follow-up phone call at 4 weeks to check on symptoms and device use.
• Return to the clinic at 3 months for a full tremor evaluation.
• Have the option to return for an additional follow-up visit at 1 year.

This study will include 5 participants with essential tremor who previously lost benefit quickly after receiving standard VIM-DBS treatment.

• Purpose: To test whether new DBS programming patterns can restore and sustain tremor control in essential tremor (ET) patients who lose benefit quickly after standard Vim-DBS.
• Hypothesis: Novel stimulation paradigms - like high-frequency, microburst, cycling, and scheduling - can overcome early habituation and provide lasting tremor improvement.
• Justification: Some ET patients experience rapid loss of benefit despite correct DBS placement. Standard programming does not help them, creating a disabling condition. Advanced programming may offer a safe, non-surgical solution.
• Objectives:
• 1. Determine if Chronos™ software programs maintain tremor improvement beyond one month.
• 2. Assess safety, tolerability, and identify the most effective stimulation parameters.
• Research Design: Prospective, single-center cohort study of 5 early-habituating ET patients. Patients trial six stimulation paradigms in clinic, then are randomized to one program for home use. Follow-up occurs at 4 weeks, 3 months, and optionally 1 year.
• Statistical Analysis: Descriptive statistics due to small sample size. Outcomes include tremor ratings, patient-reported benefit, and recurrence of habituation.

Inclusion Criteria:

• Adults with essential tremor who have undergone standard Vim-DBS surgery
• Demonstrated rapid (early) habituation to standard programming.
• Ability to provide informed consent and attend follow-up visits.

Exclusion Criteria:

• Inability to attend programming visits.
• Cognitive or language impairment precluding consent.
• Other neurological conditions confounding tremor assessment.