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Bilateral Essential Tremor Treatment With Gamma Knife

Bilateral Essential Tremor Treatment With Gamma Knife

Status
Recruiting
Phases
Phase 2Phase 3
Study type
Interventional
Source
ClinicalTrials.gov
Registry ID
NCT04748640
Acronym
BEST-GK
Enrollment
50
Registered
2021-02-10
Start date
2021-06-08
Completion date
2026-10-31
Last updated
2021-11-17

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Essential Tremor

Keywords

Gamma Knife Thalamotomy, Tremor, Essential Tremor, Dyskinesias, Neurologic Manifestations, Nervous System Diseases, Movement Disorders, Central Nervous System Diseases

Brief summary

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.

Interventions

PROCEDUREGamma Knife VIM thalamotomy

Ablation of contralateral VIM nucleus of thalamus with GK using a frame-based, Gamma Knife Perfexion or Icon unit (Elekta, Stockholm, Sweden).

Sponsors

University Health Network, Toronto
CollaboratorOTHER
Université de Sherbrooke
Lead SponsorOTHER

Study design

Allocation
NA
Intervention model
SINGLE_GROUP
Primary purpose
TREATMENT
Masking
NONE

Masking description

All assessments filmed on video and scored by a blinded evaluator.

Eligibility

Sex/Gender
ALL
Age
18 Years to No maximum
Healthy volunteers
No

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.

Design outcomes

Primary

MeasureTime frameDescription
Change in QUEST Score12 monthsDifference in QUEST score between baseline and the 12-month follow-up, with statistical significance defined as p = 0.05 and a minimum clinically important difference (MCID) defined as 5
Patient-based Assessment of Utility12 monthsA patient-reported assessment of utility after 12 months using the question Knowing what you know now, would you do this treatment again?.

Secondary

MeasureTime frameDescription
Gait Assessment (NRS-11)Baseline, post operative month 3, 6, 12, 24, 36Patient-reported and blinded observer rating of the patient's ability to walk (Numerical rating scale (NRS-11) from 0 to 10, with 10 being best)
Speech Assessment (NRS-11)Baseline, post operative month 3, 6, 12, 24, 36Patient-reported and blinded observer rating of the patient's ability to speak (Numerical rating scale (NRS-11) from 0 to 10, with 10 being best)
NumbnessBaseline, post operative month 3, 6, 12, 24, 36Incidence of new-onset numbness
DysgeusiaBaseline, post operative month 3, 6, 12, 24, 36Incidence of taste alterations
FallsBaseline, post operative month 3, 6, 12, 24, 36Number of falls in last month
Tremor (CRST)Baseline, post operative month 3, 6, 12, 24, 36Assessment of tremor using the Clinical Rating Scale for Tremor (CRST) parts A (0-88) and B (0-36), higher scores correspond to a worse tremor).
Quality of life (QUEST)Baseline, post operative month 3, 6, 12, 24, 36QUality of life in ESsential Tremor (QUEST) questionnaire (0-100 percent, higher scores correspond to a worse quality of life)
Quality of life (CRST part C)Baseline, post operative month 3, 6, 12, 24, 36Part C of the Clinical Rating Scale for Tremor (CRST) (0-32, higher scores correspond to a worse quality of life)
Health Utility (EQ-5D-5L)Baseline, post operative month 3, 6, 12, 24, 36Health Utility measured using the EQ-5D-5L and computed using the Canadian preference weights. Values range from 0 to 1, with 1 representing a perfect health.
Other adverse eventsBaseline, post operative month 3, 6, 12, 24, 36Incidence of other adverse events as classified in the CTCAE
Gait Assessment (missteps)Baseline, post operative month 3, 6, 12, 24, 36Number of missteps in a 6 m standardized tandem walk

Countries

Canada

Contacts

Primary ContactChristian Iorio-Morin
christian.iorio-morin@usherbrooke.ca819-346-1110

Outcome results

None listed

Source: ClinicalTrials.gov · Data processed: Feb 4, 2026