Bilateral Essential Tremor Treatment With Gamma Knife
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.
• 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.