Physiology, Imaging and Modeling of Essential Tremor

University of Florida

Status: Enrolling

Conditions: Essential Tremor; Dystonia; Parkinson Disease

Treatments: Device: Active biphasic pulse stimulation---VIN Biphasic; Device: Active biphasic pulse stimulation---Stimulator Off; Device: Active biphasic pulse stimulation---Home Settings

Study type: Interventional

Funder types: Other; Industry; NIH

Identifiers

NCT03811405

5R25NS108939-04 (U.S. NIH Grant/Contract)

MEDTRONIC INC (Other Identifier)

OCR19607 (Other Identifier)

IRB201802397 -N -A

Details and patient eligibility

About

This project aims to investigate novel ways to deliver brain stimulation to Essential Tremor (ET) patients by introducing software changes to their existing devices. The study team aims to investigate safety and efficacy of these new stimulation parameters in patients with ET.

Full description

Deep brain stimulation (DBS) is a neuromodulatory therapy that is effective in a subset of well selected essential tremor (ET) patients. However, as many as 1/5 of patients may initially improve, but then steadily worsen following the operation. The investigators developed a technique to study a variety of alternative stimulation methods without the use of an invasive repeat surgical intervention.

The electrophysiological effects of non-conventional DBS differ from traditional DBS, however the physiological differences in the setting of human tremor remain largely unknown. This study plans to explore gaps in knowledge of neuromodulation and will collect and contribute essential information to the underlying mechanism of action of DBS. The hypothesis of this project centers around active biphasic stimulation providing a wider therapeutic window and a lower adverse event profile as compared to conventional DBS.

Enrollment: 70 estimated patients

Sex: All

Ages: 18 to 80 years old

Volunteers: No Healthy Volunteers

Inclusion criteria

• Existing unilateral or bilateral VIN DBS for ET, non-demented (MMSE>24), and must have a documented suboptimal tremor suppression on two successive visits (compared to the baseline post-operative improvement at 6 months following ET DBS surgery). For bilateral cases, the most affected tremor side will be studied.

Exclusion criteria

• No diagnosis of Essential Tremor

Trial design

Primary purpose: Treatment

Allocation: N/A

Interventional model: Single Group Assignment

Masking: None (Open label)

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70 participants in 1 patient group

Patients with Essential Tremor

Experimental group

Description:

Patients with chronically implanted DBS devices for ET who experience progressive worsening of tremor symptoms over time. The DBS implantable pulse generator (IPG) will be loaded with a temporary custom firmware to allow implementation of active biphasic pulse stimulation. The following random conditions will be applied: (1) Home Settings; (2) VIN Biphasic; (3) Stimulator Off. A 30-minute washout period will be applied between each of the random conditions. Therefore, each patient will serve as their own control.

Treatment:

Device: Active biphasic pulse stimulation---Home Settings

Device: Active biphasic pulse stimulation---Stimulator Off

Device: Active biphasic pulse stimulation---VIN Biphasic