Demand-driven Management of Essential Tremor

University of Washington

Status: Completed

Conditions: Essential Tremor

Treatments: Device: Activa PC+S

Study type: Interventional

Funder types: Other

Identifiers

NCT02443181

STUDY00001079

Details and patient eligibility

About

This study evaluates the effectiveness of tremor control using various strategies for implementing demand-driven thalamic deep brain stimulation (DBS) for essential tremor. Therapeutic stimulation at the Vim nucleus of the thalamus will be initiated and modulated using signals derived from external sensors (e.g. EMG, accelerometer) and cortical or thalamic electrodes.

Full description

Essential tremor is effectively treated with deep brain stimulation of the ventralis intermedius nucleus of the thalamus, presumably because high-frequency stimulation disrupts aberrant cerebellar-thalamic input. For the most part, patients with essential tremor have a kinetic tremor that is present or worsened with movement. However, DBS therapy is currently continuous, and thus, stimulation occurs when the patient will not benefit symptomatically from treatment. This exposes the patient to unnecessary stimulation, which can lead to unnecessary usage of battery, unnecessary exposure to stimulation side-effects, and can possibly contribute to tolerance to DBS therapy.

One possible solution is selective stimulation when movement is required. This study will determine signals predictive of motor activity using external sensors such as EMG, and cortical biomarkers of real and imaginary movement that are well-characterized.

The primary aim is to demonstrate successful initiation and modulation of DBS therapy using the Activa PC+S system and implanted cortical or thalamic electrodes. Putative improvements in battery usage related to stimulation on-time and definition of coupling signals between thalamus and cortex that characterize tremor state are secondary outcomes.

Enrollment: 5 patients

Sex: All

Ages: 18 to 80 years old

Volunteers: No Healthy Volunteers

Inclusion criteria

• Appropriate candidates for DBS with essential tremor

Exclusion criteria

• Not meeting inclusion criteria based on tremor amplitude, neuropsychological testing, etc.
• Prior trauma to the brain on side of putative implantation of stimulator

Trial design

Primary purpose: Basic Science

Allocation: N/A

Interventional model: Single Group Assignment

Masking: None (Open label)

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5 participants in 1 patient group

Activa PC+S

Experimental group

Description:

Patients will be implanted with standard DBS electrodes for treatment of essential tremor, at the Vim nucleus of the thalamus, and an additional subdural electrode array overlying hand motor cortex.. The patient will receive standard of care programming for thalamic stimulation for essential tremor. During research study visits, implementation and evaluation of closed-loop DBS using the PC+S system will be performed.

Treatment:

Device: Activa PC+S