MRgFUS Pallidotomy for the Treatment of Task Specific Focal Hand Dystonia (TSFD) (FUS Dystonia)

February 25, 2026 updated by: University of Maryland, Baltimore

Phase 1 Clinical Trial for MR Guided Focused Ultrasound (FUS) Pallidotomy for the Treatment of Task Specific Focal Hand Dystonia (TSFD)

The purpose of this study is to assess the safety and effectiveness of MRI-guided focused ultrasound (MRgFUS) for treating task specific focal hand dystonias (TSFD). TSFD is a type of dystonia that affects hand movements during specific tasks such as writing, playing instruments or typing, often causing involuntarily movements or cramping.

Study Overview

Status

Recruiting

Detailed Description

The purpose of this study is to assess the safety and effectiveness of MRI-guided focused ultrasound (MRgFUS) for treating task specific focal hand dystonias (TSFD). TSFD refers to a condition where certain movements or tasks trigger involuntary muscle contractions, particularly during specialized and repetitive activities like writing (known as writer's dystonia), typing (typist's dystonia), playing musical instruments (musician's dystonia), or engaging in sports like golf, table tennis, or juggling. While TSFD affects around 1.2-1.5% of the general population, it's more common among athletes and musicians. Writer's dystonia, for example, typically starts with difficulty writing and hand cramping in the dominant hand, possibly spreading to the arm and shoulder muscles over time. In severe cases, the other hand may also be affected. Similarly, typist's dystonia can lead to finger flexion or extension issues during typing. Musician's dystonia is another form, seen in guitarists, pianists, harpists, or flute players, often emerging during the peak of their careers and significantly impacting musical performance. These dystonias can be career-ending as they impair performance and rarely go into remission, with onset often occurring around the age of forty.

Surgical treatments for Task-Specific Focal Dystonia (TSFD) are less often explored than for other dystonias. Thalamotomy, targeting the ventro-oralis (Vo) nucleus, has shown some promise for hand dystonias like writer's cramp or musician's dystonia. Anecdotally, some benefit from deep brain stimulation (DBS) targeting the globus pallidus internus (GPi) has also been shown, but large-scale studies for TSFD are lacking.

Another promising approach is MR guided focused ultrasound thalamotomy, a non-invasive procedure that uses real-time imaging to precisely target brain areas. This method has already shown success in treating essential tremors and Parkinson's disease symptoms. Recent studies and anecdotal cases have also demonstrated its potential for treating TSFD, with improvements in symptoms observed in patients with writer's cramp, musician's dystonia, and other related conditions.

The Exablate MR Guided Focused Ultrasound Transcranial system is a device designed to overcome the limitations of delivering ultrasound through the intact skull. It uses advanced technology like water-cooling, acoustic correction algorithms, and patient-specific CT data to ensure precise and safe delivery of ultrasound energy to targeted brain areas. This pilot study protocol aims to utilize MR guided focused ultrasound thalamotomy as a treatment option for TSFD.

Study Type

Interventional

Enrollment (Estimated)

10

Phase

  • Not Applicable

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Contact

  • Name: Dheeraj Gandhi, MD
  • Phone Number: (248)-497-8856
  • Email: dgandhi@umm.edu

Study Contact Backup

Study Locations

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Ages Eligible for Study

  • Adult
  • Older Adult

Accepts Healthy Volunteers

No

Description

Inclusion Criteria:

  1. Clinical diagnosis of moderate to severe TSFD with impact in their daily function or occupation function
  2. Patients who failed to response or had unsatisfactory response to the first treatment, such as Botulinum toxin treatment or DBS or refuse these alternative options
  3. Age greater than 21 and less than 75 years
  4. Subjects who are able and willing to give consent and able to attend all study visits,
  5. Documented chronic, symptoms for more than 6 months duration
  6. Pallidotomy is feasible based on evaluation of imaging studies
  7. Patient able to communicate sensations during the ExAblate TcMRgFUS treatment
  8. Two members of the medical team have agreed upon inclusion and exclusion criteria

Exclusion Criteria:

  1. Patient with contraindications to MRI such as severe claustrophobia and metallic implants incompatible with MRI.
  2. Presence of generalized dystonia or involvement of two or more contiguous body regions (such as Arm along with neck)
  3. Severe psychiatric disorder such as uncontrolled depression, anxiety, bipolar disorder, prior attempt at suicide or suicide ideation in preceding 12 months
  4. Life expectancy less than 12 months
  5. Anticoagulant or antiplatelet medications as well as underlying coagulopathy
  6. Pregnant ladies or women of childbearing age who are sexually active and not using contraception
  7. Inability to provide informed consent, for example due to underlying cognitive impairment or aphasia
  8. Presence of intracranial mass or an acute intracranial abnormality
  9. Subjects with unstable cardiac status such as unstable angina pectoris, documented myocardial infarction within 6 months of protocol entry or ejection fraction less than 40
  10. Subjects exhibiting any behavior(s) consistent with ethanol or substance abuse as defined by the criteria outlined in the Diagnostic and Statistical Manual of Mental Disorders(DSM-IV)
  11. Severe hypertension (diastolic blood pressure > 100 on medication or persistently elevated systolic blood pressure>140 mmHg despite adequate antihypertensive medications)
  12. History of intracranial hemorrhage, traumatic brain injury or thalamic stroke.
  13. Cerebrovascular disease (multiple cerebrovascular accident's (CVA) or CVA within 6 months)
  14. Subjects with life-threatening systemic disease that include and not limited to the following will be excluded from the study participation: HIV, Liver Failure, blood dyscrasias, etc.
  15. Subjects with a history of seizures within the past year
  16. Individuals who are not able or willing to tolerate the required prolonged stationary supine position during treatment (can be up to 4 hours of total table time.)

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Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

  • Primary Purpose: Device Feasibility
  • Allocation: N/A
  • Interventional Model: Single Group Assignment
  • Masking: None (Open Label)

Arms and Interventions

Participant Group / Arm
Intervention / Treatment
Experimental: ExAblate Transcranial treatment
The ExAblate Transcranial system will be used to destroy a small cluster of cells that may be causing the study participant's pain . The ExAblate uses ultrasound to heat a small spot in the brain called globus pallidus internus(GPi). Ultrasound passes through the skin and skull and into the brain to focus on this particular spot.
The ExAblate Transcranial system will be used to destroy a small cluster of cells that may be causing the study participant's dystonia . The ExAblate uses ultrasound to heat a small spot in the brain called globus pallidus internus(GPi). Ultrasound passes through the skin and skull and into the brain to focus on this particular spot.
Other Names:
  • The ExAblate® MR guided focused ultrasound system

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Incidence of Treatment related adverse events
Time Frame: All events will be reported up to 6 months from treatment
Procedure related or device related adverse events will be reported, from the treatment day through the 6-month follow-up period.
All events will be reported up to 6 months from treatment

Secondary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Change in dystonia intensity
Time Frame: 6 Months
Efficacy of ExAblate TcMRgFUS for pallidotomy will be evaluated using Arm disability dystonia scale (ADDS) and scales specific to writer's cramp (WCRS) or musician's dystonia (TMDS) scores.
6 Months
Change in patient's perception of quality of life
Time Frame: 6 months
Quality of life assessments will be performed with short form (SF)-36 survey
6 months
Change in patient's perception of the effect of the procedure
Time Frame: 6 Months
Patient Global impression of change (PGIC): The effect of the procedure on patient perceived impact of pain related symptoms, emotions and quality of life will be measured using PGIC scale.
6 Months

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (Actual)

June 10, 2024

Primary Completion (Estimated)

June 1, 2027

Study Completion (Estimated)

June 1, 2028

Study Registration Dates

First Submitted

April 11, 2024

First Submitted That Met QC Criteria

April 11, 2024

First Posted (Actual)

April 16, 2024

Study Record Updates

Last Update Posted (Actual)

February 27, 2026

Last Update Submitted That Met QC Criteria

February 25, 2026

Last Verified

February 1, 2026

More Information

Terms related to this study

Plan for Individual participant data (IPD)

Plan to Share Individual Participant Data (IPD)?

NO

Drug and device information, study documents

Studies a U.S. FDA-regulated drug product

No

Studies a U.S. FDA-regulated device product

Yes

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

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