NCT06331052 · University of North Carolina, Chapel Hill
3-D Tractography FUS Ablation for Essential Tremor
What this study is about
The investigators propose to advance Vim-FUSA (Ventral Intermediate Nucleus - Focused Ultrasound Ablation) with the support of 3-D tractography, a neuroimaging technique to visually represent nerve tracts within the brain. The investigators hypothesize that 3-D tractography Vim-FUSA will improve the Vim ablation compared to standard Vim-FUSA and prove safe and feasible in the clinical setting.
View original scientific description
The investigators propose to advance Vim-FUSA (Ventral Intermediate Nucleus - Focused Ultrasound Ablation) with the support of 3-D tractography, a neuroimaging technique to visually represent nerve tracts within the brain. The investigators hypothesize that 3-D tractography Vim-FUSA will improve the Vim ablation compared to standard Vim-FUSA and prove safe and feasible in the clinical setting. The investigators also hypothesize that intraoperative magnetic resonance (i-MR) monitoring will differentiate ablated tissue from immediate perilesional edema and accurately predict the Vim-FUSA clinical outcomes.
Interventions
DEVICE
MR-guided Focused Ultrasound Ablation
3-D tractography Vim-FUSA -D tractography Vim-FUSA will be carried out as follows: (a) head shaving and placement of the stereotactic frame (Integra radionics frame, Integra Lifesciences, NJ, USA) secured to the skull with transcutaneous screws; (b) positioning on the procedure table and placement of the ultrasound transducer; (c) acquisition of conventional magnetic resonance (MR) imaging and co-registration with the CT head and 3-D tractography imaging acquired pre-surgically; (d) exploration of the target area with subtherapeutic sonications; (e) intraoperative monitoring with clinical testing of tremor and side effects with a standardized protocol. (f) Therapeutic sonications in the target area to deliver definitive ablation followed by clinical testing of tremor and side effects with a standardized protocol as described in section (e).
Primary outcome measures
Number of Participants without Side Effects
Time frame: during the surgical procedure
Feasibility is defined as the ability to complete the procedure without side effects.
Absolute Change in Tremor
Time frame: Baseline, Month 3
The absolute change from baseline to Month 3 follow-up in upper extremity Tremor-Motor scores for the treated side is a sub-scale of Clinical Rating Scale for Tremor (CRST) Part A and Part B sum used to measure treated-side upper extremity tremor changes over time. Tremor-motor scores range from 0-32 points. Individual subject's scores at Baseline and 3 Months used to calculate absolute change from baseline and averaged across subjects. High absolute change from baseline is better (shows improvement).
Relative Change in Tremor
Time frame: Baseline, Month 3
The relative change from baseline to Month 3 follow-up in upper extremity Tremor-Motor scores for the treated side is a sub-scale of Clinical Rating Scale for Tremor (CRST) Part A and Part B sum used to measure treated-side upper extremity tremor changes over time. Tremor-motor scores range from 0-32 points. Individual subject's scores at Baseline and 3 Months used to calculate relative change from baseline and averaged across subjects. High relative change from baseline is better (shows improvement).
Who can participate
This study lists these criteria on ClinicalTrials.gov. A study coordinator reviews eligibility during screening — this page does not determine whether you qualify.
Inclusion criteria
- Diagnosis of moderate to severe ET agreed upon by at least two movement disorder trained physicians
- Symptoms refractory to at least two medications
- Stable medication regimen for at least 4 weeks prior to screening
- Willing and able to participate in all follow-up visits
- Willing and able to undergo MR imaging.
Exclusion criteria
- Uncontrolled hypertension
- Medically unstable coronary artery disease
- Coagulopathy, anticoagulant therapy, or inability to temporarily stop any antithrombotic medication
- Tremor disorders other than ET
- Unwilling or unable to undergo tremor surgery while awake
- Significant and non-correctible motion artifact in imaging
- Pregnant at the time of enrollment or preoperative evaluation
- History of psychosis
- History of drug or alcohol abuse
- Prior brain surgery such as Vim-FUSA, deep brain stimulation, and gamma knife thalamotomy
- Botulinum toxin injection in the tremor-impacted areas three months prior to the baseline assessment and until 3-months after Vim-FUSA
- Skull density ratio lower than 0.4
- Does not qualify for FDA-approved clinical use based on current FDA labeling
- Any significant issue raised by the neurologist or neurosurgeon that may compromise participant safety or potentially interfere with study interpretation.
Where
- Chapel Hill, North Carolina
Collaborators
Texas Tech University Health Sciences Center, El Paso, University of Pittsburgh, National Institute of Neurological Disorders and Stroke (NINDS)
Related conditions & keywords
Frequently asked questions
What is a clinical trial?
A clinical trial is a research study that tests new medical treatments, drugs, devices, or procedures to determine their safety and effectiveness. Trials are carefully designed and monitored to protect participants while advancing medical knowledge.
Is it safe to participate?
Clinical trials follow strict safety guidelines and ethical standards. Trials must be reviewed and approved, and participants are closely monitored by medical professionals throughout the study. You can withdraw at any time if you choose.
Will I be compensated?
Many clinical trials offer compensation for your time, travel expenses, and inconvenience. The specific compensation varies by study and will be discussed during the screening process. All study-related medical care is typically provided at no cost to participants.
Will I receive a placebo instead of treatment?
When effective treatment exists, participants typically receive either the standard treatment plus the study intervention, or the standard treatment plus placebo. You would not be denied effective care. Placebos are primarily used when no proven treatment is available, or in addition to standard care. Your trial consent form will clearly explain what treatments you may receive.
Can I leave a trial if I change my mind?
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How long does a clinical trial last?
Trial duration varies widely depending on the study design and purpose. Some trials last just a few weeks, while others may continue for months or years. The study coordinator will provide specific timeline information during your screening call.
Data: ClinicalTrials.gov · synced Jan 20, 2026 · Source of record for eligibility and locations