Simultaneous Bilateral Radiofrequency Thalamotomy for Medication-Refractory Essential Tremor

NCT07066358 | Recruiting

• 1 other identifier: TWMU-Vim01
• Study Type: interventional
• Target: 5
• Locations: 1 country
• Sites: 1

Brief Summary

This study aims to evaluate the safety and effectiveness of simultaneous bilateral radiofrequency thalamotomy for patients with medication-refractory essential tremor (ET). Essential tremor is a common neurological condition that causes involuntary shaking, often affecting the hands and interfering with daily activities such as writing, eating, or using tools. While medications such as propranolol and primidone can help some patients, others experience limited or no benefit. In this study, five adult participants diagnosed with essential tremor that does not respond to standard medications will undergo simultaneous bilateral stereotactic radiofrequency lesioning of the ventral intermediate nucleus (Vim) of the thalamus. This procedure involves precisely targeting both sides of the Vim to reduce tremor in both arms during a single surgical session. Prior to surgery, participants will undergo brain MRI for surgical planning, as well as clinical evaluations including the Clinical Rating Scale for Tremor (CRST), Quality of Life in Essential Tremor Questionnaire (QUEST), the Scale for the Assessment and Rating of Ataxia (SARA), mood scales (BDI, BAI, AES), and cognitive function testing. The surgery will be performed under local anesthesia using a stereotactic frame and intraoperative imaging. Tremor reduction will be assessed postoperatively and at 1, 3, and 6 months. The primary outcome is the improvement in CRST scores at 6 months. Secondary outcomes include quality of life (QUEST), ataxia symptoms (SARA), mood and cognitive changes, and adverse events. This research is being conducted at Tokyo Women's Medical University. The study is IRB-approved and participants will be monitored closely throughout the 6-month follow-up period. Any complications or adverse events, such as temporary speech or swallowing difficulties, will be recorded and managed appropriately. The goal of this study is to explore whether performing thalamotomy on both sides simultaneously is a safe and effective treatment option for patients with severe and medication-resistant essential tremor.

Conditions

Essential Tremor

Keywords

thalamotomy; intraoperative MRI

Outcome Measures

Primary Outcomes (1)

• Change in Clinical Rating Scale for Tremor (CRST) Score From Baseline to 6 Months Postoperatively

  The Clinical Rating Scale for Tremor (CRST) is a standardized scale used to evaluate tremor severity and its impact on motor function and activities of daily living. The total CRST score includes postural and action tremor, writing, pouring tasks, and disability ratings. Higher scores indicate greater severity. The primary outcome is the change in total CRST score from preoperative baseline to 6 months after the bilateral radiofrequency thalamotomy.

  Baseline and 6 Months After Surgery

Secondary Outcomes (5)

• Change in QUEST Score From Baseline to 6 Months Postoperatively

  Baseline, 1 Month, 3 Months, and 6 Months After Surgery

• Change in SARA Score From Baseline to 6 Months Postoperatively

  Baseline, 1 Month, 3 Months, and 6 Months After Surgery

• Change in BDI Score From Baseline to 6 Months Postoperatively

  Baseline and 6 Months After Surgery

• Change in BAI Score From Baseline to 6 Months Postoperatively

  Baseline and 6 Months After Surgery

• Change in AES Score From Baseline to 6 Months Postoperatively

  Baseline and 6 Months After Surgery

Study Arms (1)

Bilateral RF Thalamotomy

EXPERIMENTAL

Participants in this arm will undergo simultaneous bilateral radiofrequency lesioning of the ventral intermediate nucleus (Vim) of the thalamus using a stereotactic frame under local anesthesia. The procedure begins with treatment on the side contralateral to the dominant hand. Intraoperative MRI will be performed after the first lesion to confirm the absence of hemorrhagic complications. If no complications are observed, the procedure will continue on the opposite side. If hemorrhage is detected, the surgery will be terminated after unilateral treatment. The goal of this intervention is to reduce medication-refractory tremor in both upper limbs.

Procedure: Simultaneous Bilateral RF Thalamotomy

Interventions

Simultaneous Bilateral RF Thalamotomy PROCEDURE

This intervention involves simultaneous bilateral radiofrequency (RF) lesioning of the ventral intermediate nucleus (Vim) of the thalamus using a stereotactic frame under local anesthesia. The procedure begins with RF ablation on the side contralateral to the dominant hand. Intraoperative MRI is then performed to confirm the absence of hemorrhagic complications. If no bleeding or other adverse events are detected, the procedure proceeds to the contralateral Vim. If hemorrhage is identified, the surgery is terminated after unilateral treatment. This technique allows for immediate bilateral tremor reduction in patients with medication-refractory essential tremor, while prioritizing patient safety through intraoperative imaging-based decision-making.

Bilateral RF Thalamotomy

Eligibility Criteria

• Age: 20 Years - 70 Years
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Adults aged 20 to 70 years.
• Diagnosis of essential tremor by a neurologist or neurosurgeon specializing in movement disorders.
• Refractory to standard pharmacological therapy (e.g., propranolol, primidone, benzodiazepines, or alprenolol).
• Mini-Mental State Examination (MMSE) score ≥ 27.
• Able to undergo MRI.
• Provided written informed consent for participation in the study.

You may not qualify if:

• History or evidence of bleeding tendency.
• MRI contraindications (e.g., metallic implants, severe claustrophobia).
• Presence of intracranial pathology on preoperative MRI that would interfere with surgery.
• Pregnant or breastfeeding individuals.
• Any other condition that the principal investigator deems inappropriate for study participation.

Sponsors & Collaborators

• Tokyo Women's Medical University: lead

Study Sites (1)

Tokyo Women's Medical University, Department of Neurosurgery

Shinjuku-Ku, Tokyo, 1628666, Japan

RECRUITING

MeSH Terms

Conditions

Essential Tremor

Condition Hierarchy (Ancestors)

Movement Disorders; Central Nervous System Diseases; Nervous System Diseases

Study Officials

• Shiro HORISAWA, MD

  Tokyo Women's Medical University

  PRINCIPAL INVESTIGATOR

Central Study Contacts

SHIRO Horisawa, MD

CONTACT

+81333538111; neurosurgery0222@gmail.com

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: NA
• Masking: NONE
• Purpose: TREATMENT
• Intervention Model: SINGLE GROUP
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Assistant Professor, Department of Neurosurgery

Model Details: All enrolled participants will receive simultaneous bilateral radiofrequency lesioning of the ventral intermediate nucleus (Vim) of the thalamus in a single surgical session. No control or comparator group is included.

Study Record Dates

• First Submitted: July 4, 2025
• First Posted: July 15, 2025
• Study Start: July 3, 2025
• Primary Completion (Estimated): October 1, 2026
• Study Completion (Estimated): December 1, 2026
• Last Updated: July 18, 2025

Record last verified: 2025-07

Data Sharing

• IPD Sharing: Will share
• Shared Documents: STUDY PROTOCOL
• Time Frame: The data will be available beginning 6 months after publication of the study results in a peer-reviewed journal and will be available for 5 years.
• Access Criteria: Qualified researchers may request access to the de-identified individual participant data and supporting documents (Study Protocol, SAP, ICF). Access will be granted after approval by the principal investigator and a data use agreement.

Locations

JP (1)