Bilateral Essential Tremor Treatment With Gamma Knife (BEST-GK)

Université de Sherbrooke

Status and phase: Enrolling; Phase 3; Phase 2

Conditions: Essential Tremor

Treatments: Procedure: Gamma Knife VIM thalamotomy

Study type: Interventional

Funder types: Other

Identifiers

NCT04748640

20-5172

Details and patient eligibility

About

Combined Phase II/III, multi-center, prospective, single-blinded trial.

Ten (10) patients with essential tremor who previously underwent successful and uncomplicated GK thalamotomy for essential tremor will undergo a contralateral treatment. The incidence of side effects will be determined at 3 months postoperatively, graded per the CTCAE v5 and analyzed by a data safety monitoring board. Upon successful review, this Phase II trial will be converted to a Phase III trial of utility that will enrol 40 additional patients. The primary outcome will be the change in QUEST score at 12 months postoperatively, as well as a patient-reported assessment of Health Utility. Secondary outcomes will include objective tremor, gait and speech assessments (filmed and scored by blinded evaluators), as well as quality of life questionnaires and adverse events questionnaires. Outcomes will be assessed at baseline, as well as 3, 6, 12, 24 and 36 months post-operatively.

Enrollment: 50 estimated patients

Sex: All

Ages: 18+ years old

Volunteers: No Healthy Volunteers

Inclusion criteria

• Patients must be ≥ 18 years
• The patient has a primary diagnosis of ET or ET plus confirmed by a movement disorder neurologist;
• The patient previously underwent a GK thalamotomy (> 12 months ago);
• The tremor on the untreated side negatively impacts the patients' quality of life;
• The patient wants treatment of the contralateral side.

Exclusion criteria

• Clinically relevant gait and/or balance impairment (e.g. wide-based, more than 2 falls/months, wheelchair, walker, cane use);
• Clinically relevant speech impairment (e.g. impairment of intelligibility);
• Inability to comply with the follow-up schedule;
• Refusal of the treating physician.

Trial design

Primary purpose: Treatment

Allocation: N/A

Interventional model: Single Group Assignment

Masking: None (Open label)

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50 participants in 1 patient group

Treatment group

Experimental group

Description:

Participants will undergo a thalamotomy contralateral to their previous treatment with Gamma Knife using a frame-based, Gamma Knife Perfexion or Icon unit (Elekta, Stockholm, Sweden).

Treatment:

Procedure: Gamma Knife VIM thalamotomy