Directional Versus Nondirectional DBS for ET

Not Applicable

• Conditions: Essential Tremor
• Interventions: Device: Deep brain stimulation of the VIM Thalamic nuclei

• Registration Number: NCT04828798
• Lead Sponsor: Oregon Health and Science University

Brief Summary

This will be a single center (OHSU) proof of concept trial to demonstrate that directional deep brain stimulation (DBS) creates a larger therapeutic window for the treatment of essential tremor (ET), effectively treats ET, and minimizes effects on speech, gait and balance compared to nondirectional DBS.

Detailed Description

Specific Aims:

1. To compare the therapeutic window (TW) of directional versus nondirectional deep brain stimulation for treatment of tremor.

Hypothesis: directional DBS will result in a wider TW than nondirectional DBS.

2. To compare the effects of directional versus nondirectional DBS on speech Hypothesis: Objective and subjective speech impairment will occur to a greater extent in nondirectional DBS versus directional DBS optimized for tremor control.

3. To compare the effects of directional versus nondirectional DBS on balance and gait Hypothesis: Objective and subjective balance and gait impairment will occur to a greater extent in nondirectional DBS versus directional DBS optimized for tremor control.

4. To assess efficacy for tremor of nondirectional and directional DBS in an optimized programming configuration Hypothesis: both directional and nondirectional DBS will significantly improve tremor compared to baseline.

Study Timeline

• Study First Submitted: 2021-02-08
• Status Verified: 2021-03
• Study First Submitted QC: 2021-03-30
• Last Update Submitted: 2021-03-30
• Study Start: 2021-04-01
• Study First Posted: 2021-04-02
• Last Update Posted: 2021-04-02
• Primary Completion: 2023-08-08
• Study Completion: 2024-02-08

Recruitment & Eligibility

• Status: UNKNOWN
• Sex: All
• Target Recruitment: 24

Inclusion Criteria

• A tremor syndrome of bilateral upper limb action tremor with at least 3 years' duration

Exclusion Criteria

• Patients who have decided not to receive DBS for control of their medication-refractory essential tremor.
• Patients with secondary tremor (ie not Essential Tremor), such as side effects from medications, secondary to another identified neurologic disease (eg multiple sclerosis, -----Parkinson's disease, dystonia).
• Prior history of deep brain stimulation.
• Prior history of thalamotomy.
• A history or signs of dystonia, ataxia or parkinsonism.
• Task specific tremor.
• Orthostatic tremor.
• Patients with cardiac pacemakers, defibrillators, or neurostimulators.
• Patients who require MRI, ECT, rTMS, or diathermy.
• Subjects with other type of neurological disease or injury.

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: CROSSOVER

Arm && Interventions

Group	Intervention	Description
Nondirectional deep brain stimulation	Deep brain stimulation of the VIM Thalamic nuclei	Deep brain stimulation delivered in a nondirectional manner within an axial plane
Directional deep brain stimulation	Deep brain stimulation of the VIM Thalamic nuclei	Deep brain stimulation delivered in a directional manner within an axial plane

Primary Outcome Measures

Name	Time	Method
Therapeutic window	3 months	Range of therapeutic current from clinical improvement to side effect threshold, measured in milliamps, within a range of 0.0 to 5.0 milliamps

Secondary Outcome Measures

Name	Time	Method
Improvement of tremor	3 months	Change in The Essential Tremor Rating Scale (TETRAS) combined score. Range = 0 to112. Higher score = worse outcome.
Compare the effects of directional versus nondirectional DBS on self perception of speech	3 months	Self Perception of speech: Subjects will rate their "ability to speak" on a VAS (from 0 \[normal\] to 100 mm \[worst\]) in each condition.
Compare the effects of directional versus nondirectional DBS on balance and gait	3 months	The Activities-specific Balance Confidence (ABC) scale is a 16-item self-report measure in which participants rate their balance confidence on a 0-100 scale (0 = 0 no confidence, 100 = 100 complete confidence).
Compare the effects of directional versus nondirectional DBS on perceptual assessment of voice and speech	3 months	Perceptual assessment of voice and speech will be completed with listeners judging a reading sample using a 100mm Visual Analog Scale (VAS).

Trial Locations

Locations (1)

Oregon Health & Science University; 🇺🇸 Portland, Oregon, United States