Essential Tremor
Conditions
Interventions
ExAblate MR Guided Focused Ultrasound is an attractive modality for non-invasive thermal ablation of soft tissue tumors [1-6]. Treatment begins by acquiring a series of MR images of the target tissue
Sponsors
Departments of Neurology and Neurosurgery, Hokuto Hospital
Eligibility
Sex/Gender
All
Inclusion criteria
Inclusion criteria: 1. Men and women age 22 years or older 2. Subjects who are able and willing to give consent and able to attend all study visits. 3. A diagnosis of ET as confirmed from clinical history and examination by a neurologist or neurosurgeon specialized in movement disorder 4. Have had an inadequate response to one or two oral doses of medication, per local standards. An inadequate medication trial is defined as a therapeutic dose of each medication and poor response to drug, or the development of side effects as the medication dose is titrated. 5. Following the 1-month medication stability period, subject must be on stable medication for tremor a. The 1-Month stability period visit will be 1-month post consent date 6. Vim nucleus of thalamus can be target by the ExAblate device. The thalamic region must be apparent on MRI such that targeting can be performed by measurement from a line connecting the anterior and posterior commissures of the brain. 7. Able to communicate sensations during the ExAblate TcMRgFUS treatment 8. Postural or intention tremor severity score of greater than or equal to 2 in the dominant hand/arm as measured by the CRST rating scale while stable on medication. 9. May have bilateral appendicular tremor 10. Significant disability due to essential tremor despite medical treatment (CRST score of 2 or above in any one of the items 16-23 from the Disability subsection of the CRST: [speaking, feeding other than liquids, bringing liquids to mouth, hygiene, dressing, writing, working, and social activities]) 11. Inclusion and exclusion criteria have been agreed upon by two members of the medical team. 12. Subjects on stable antidepressant medications for at least 3 months may be enrolled into this study (i.e., no change in medication drug or dosage for 3 months).
Exclusion criteria
Exclusion criteria: 1. Subjects with unstable cardiac status 2. Subjects exhibiting any behaviors consistent with ethanol or substance abuse 3. Severe hypertension 4. Subjects with standard contraindications for MR imaging 5. Known intolerance or allergies to the MRI contrast agent 6. Patient with severely impaired renal function and/or who is on dialysis 7. History of abnormal bleeding and/or coagulopathy 8. Receiving anticoagulant or antiplatelet therapy within one week of focused ultrasound procedure or drugs known to increase risk or hemorrhage within one month of focused ultrasound procedure 9. Active or suspected acute or chronic uncontrolled infection 10. History of immunocompromise including those who are HIV positive 11. History of intracranial hemorrhage 12. Cerebrovascular disease 13. Subjects with uncontrolled symptoms and signs of increased intracranial pressure 14. Presence of any other neurodegenerative disease such as Parkinson-plus syndromes suspected on neurological examination 15. Anyone suspected to have the diagnosis of idiopathic Parkinson's disease 16. Presence of significant cognitive impairment 17. Subjects with life-threatening systemic disease 18. Subjects with a history of seizures within the past year 19. Subjects with presence or history of psychosis. Subjects with significant or active mood disorders including depression 20. Subjects with risk factors for intraoperative or postoperative bleeding 21. Subjects with brain tumors 22. Pregnancy or lactation 23. Subjects who have had deep brain stimulation or a prior stereotactic ablation of the basal ganglia 24. Subjects who have been administered botulinum toxins for 5 months prior to Baseline 25. Subjects who have an Overall Skull Density Ratio of 0.35 or less as calculated from the screening CT
Design outcomes
Primary
| Measure | Time frame |
|---|---|
| 1. Safety Safety of ExAblate will be determined by an evaluation of the incidence and severity of device / treatment related complications from the first treatment day visit through ALL study follow ups. Adverse events (type, frequency, severity) are expected to be similar to those of previous studies using ExAblate TcMRgFUS for Thalamotomy. All AEs will be reported and categorized by investigators as definitely, probably, possibly, or unrelated to the device or procedure and categorized by treatment group / treatment arm. 2. Effectiveness Primary effectiveness will be evaluated using a validated, tremor rating scale: the Clinical Rating Scale for Tremors (CRST) for ET subjects, based upon subjects in whom unilateral ExAblate lesioning is attempted (i.e., Intent-to-Treat analysis). Clinical assessments will be made at the following time points: screening, baseline with subjects on confirmed stable medication (at 1-months post screening), and post-treatment at 1 week, 1 month, 3 months, 6 months, and 12 months. | — |
Secondary
| Measure | Time frame |
|---|---|
| 1. Quality life claims: Questionnaire for Essential Tremor (QUEST) outcome (upper extremity questions) at Months 3 change from Baseline 2. Durability (as measured by QUEST upper arm extremity questions) of the procedure as reflected by the efficacy data through change from baseline measures through Month 12 follow up 3. Subject daily functionalities: as measured by CRST Part-C (subscales) Month 12 as compared to Baseline | — |
Countries
Japan
Contacts
Public ContactYu-ichi Tsutsumi
Hokuto Hospital Employee Relations Division
Outcome results
None listed