Transcranial Direct Current Stimulation of the Motor Cortex in Essential Tremor

Transcranial Direct Current Stimulation of the Motor Cortex in Essential Tremor : A Randomized Controlled Pilot Study

The current research is aimed at using Transcranial Direct Current Stimulation (tDCS) as complementary therapeutic tool in the treatment of essential tremor. Patients will be randomized into two groups (tDCS-cathode vs. tDCS-sham) according to detailed protocol. Main outcome will be measured by the change in tremor amplitude using an accelerometer pre and post cathodal tDCS of the motor cortex.

A total of 40 patients ought to be enrolled as specified in methodology. Secondary outcomes will assess TRG essential tremor rating assessment scale (TETRAS) as well as clinical monitoring.

Study Overview

• Status: Unknown
• Conditions: Essential Tremor; Transcranial Direct Current Stimulation
• Intervention / Treatment: Device: transcranial direct current stimulation

Detailed Description

Essential tremor (ET) is a common progressive neurological disorder and is the most common movement disorder. Worldwide , up to 5% of the population suffer from this disorder with an increased incidence with advanced age.

The proposed mechanism that underlies ET, the central oscillating network, is mainly composed of the olivocerebellar system, thalamus and motor cortex. An interruption in this circuit limits the ability of the cortex to reorganize and restore ET. a case of 76 year old female with essential tremor that disappeared following a cortico-subcortical prerolandic stroke despite complete motor recovery highlights the role of the motor cortex in the production and possible therapeutic role of the transcranial direct current stimulation.

Study design A randomized, sham-controlled, double blind and crossover study.

Study procedure:

The first visit is an inclusion visit Prior to starting the first tDCS session, the patient will be asked to fill his/her first TRG essential tremor assessment (TETRAS) scale. The physician will then quantitatively analyze the tremor on the most affected side using an accelerometer. Cathodal tDCS will be administered on the area representing the primary motor cortex and the anode over the contralateral supraorbital area. tDCS stimulation (cathodal and sham) will be done daily for 5 consecutive days during weeks 1 and 5. Each stimulation session will last 30 minutes. tDCS will be performed while the patient is at rest, without any concurrent cognitive or motor task.The two tDCS sessions will be separated by a 23 day washout period.

Patient will be asked to fill out their TETRAS at days 1 and 5 of each tDCS session (cathodal and sham), and days 12 and 19 after each tDCS session (cathodal and sham).

Accelerometer assessment of the tremor will be performed at days 1 and 5 of each tDCS stimulation session (cathodal and sham).

• Study Type: Interventional
• Enrollment (Anticipated): 40
• Phase: Not Applicable

Contacts and Locations

• Study Contact: Name: Naji Riachi, MD; Phone Number: 6312 009611200800; Email: Naji.riachi@lau.edu.lb

Study Locations

• Lebanon
  • Beirut, Lebanon
    • Recruiting
    • LAUMCRH
    • Contact: Naji Riachi, MD; Phone Number: 6312 009611200800; Email: Naji.riachi@lau.edu

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years and older (Adult, Older Adult)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

Description

Inclusion Criteria:

- Patients who fulfil the 2017 Movement society concusses statement criteria for essential tremor

Exclusion Criteria:

• Isolated focal tremor (voice, head)
• Orthostatic tremor with a frequency of more than 12 Hz
• Task and position specific tremor
• Sudden onset and stepwise deterioration of tremor
• History of substance abuse or dependence in the past
• Co-morbid medical conditions capable of producing or enhancing tremors
• Use of a medication with potential effect on tremor
• History of neurological disorders, brain tumors, brain surgery or abnormal neurological examination
• Epileptic disorders
• Cardiac pacemakers
• Metallic hardware in the head or scalp (surgical clips)
• Eczema or skin abrasion at the intended site of stimulation
• Currently pregnant or plan for pregnancy in the next 6 months
• Patients with prior experience with tDCS
• Major psychosocial problems or medical problems rendering informed consent impossible

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Crossover Assignment
• Masking: Triple

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Active Comparator: Active tDCs; Active tDCS will be administered through a pair of conductive rubber electrodes covered by saline soaked sponges (35 cm2). The current will be delivered continuously at 2 mA for 30 min through a battery-driven constant-current stimulator. The cathode will be positioned facing the primary motor cortex area and the anode over the contralateral supraorbital area.	Device: transcranial direct current stimulation; tDCS will be administered through a pair of conductive rubber electrodes covered by saline soaked sponges (35 cm2). The current will be delivered continuously at 2 mA for 30 min through a battery-driven constant-current stimulator (Sooma Oy, Helsinki, Finland).
Sham Comparator: Sham tDCS; Sham stimulation will be delivered to the motor cortex using a sham tDCS device that delivers a direct current for 10 seconds at the beginning and end of tDCS to provide sensory experiences similar to active stimulation.	Device: transcranial direct current stimulation; tDCS will be administered through a pair of conductive rubber electrodes covered by saline soaked sponges (35 cm2). The current will be delivered continuously at 2 mA for 30 min through a battery-driven constant-current stimulator (Sooma Oy, Helsinki, Finland).

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Tremor amplitude	Change in tremor amplitude using an accelerometer pre and post cathodal tDCS of the motor cortex.	5 days

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Functional impact of tremor	Assess change from baseline of the functional impact of tremor using the TETRAS scale	19 days

Collaborators and Investigators

• Sponsor: Lebanese American University
• Investigators: Principal Investigator: Rechdi Ahdab, Lebanese American University Medical Center

Study record dates

Study Major Dates

• Study Start (Actual): July 19, 2019
• Primary Completion (Anticipated): June 1, 2021
• Study Completion (Anticipated): October 1, 2021

Study Registration Dates

• First Submitted: May 14, 2019
• First Submitted That Met QC Criteria: May 14, 2019
• First Posted (Actual): May 16, 2019

Study Record Updates

• Last Update Posted (Actual): August 13, 2019
• Last Update Submitted That Met QC Criteria: August 12, 2019
• Last Verified: August 1, 2019

More Information

Terms related to this study

• Keywords: primary motor cortex
• Additional Relevant MeSH Terms: Central Nervous System Diseases; Nervous System Diseases; Neurologic Manifestations; Movement Disorders; Dyskinesias; Tremor; Essential Tremor
• Other Study ID Numbers: LAUMCRH.RA3.11/Apr/2019

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: Yes
• product manufactured in and exported from the U.S.: Yes