Essential Tremor
Conditions
Brief summary
A feasibility Study to Evaluate Safety and Initial Effectiveness of ExAblate Transcranial MRI-guided focused ultrasound (MRgFUS) treatment of patients with medication-refractory movement disorders, namely Essential Tremor (ET). This study is designed as a prospective, single site, single arm, nonrandomized study. Assessments will be made before and three months after MRgFUS for clinical symptom relief, quality of life (QoL) improvements, and safety of MRgFUS in the treatment of ET. Similarly, QoL measures will be obtained using Quality of Life in Essential Tremor (QUEST) questionnaire. Relative Safety will be evaluated using a common description of Significant Clinical Complications for patients treated in this study. This study will be performed on the 3T MR scanners. The ExAblate system is a medical device that involves a focused ultrasound system and an MRI scanner. ExAblate delivers a pulse of focused ultrasound energy, or sonication, to the targeted tissue. In this particular study the targeted tissue is a unilateral thermal lesion created in the ventralis intermedius nucleus of the thalamus. The treatment begins with a series of standard diagnostic MR images to identify the location and shape of tumor to be treated. The ExAblate computer uses the physician's designation of the target volume to plan the best way to cover the target volume with small spots called sonications. These treatment spots are cylinder shaped. Their size depends on sonication power and duration. During the treatment, a specific MR scan, which can be processed to identify changes in tissue temperature, provides a thermal map of the treatment volume to confirm the therapeutic effect. The thermal map is used to monitor the treatment in progress, and confirm that the ablation is proceeding according to plan, thus closing the therapy loop. The ExAblate transcranial operates a helmet-shaped transducer (currently utilizing 1000-element phased array transducer) positioned above the subject head. The ExAblate transcranial system also includes means to immobilize the subject head, cool the interface water, and software for CT analysis and phase correction computation. The ExAblate transcranial system is an experimental device and is being investigated in this study.
Interventions
Sponsors
InSightec
Study design
Allocation
NON_RANDOMIZED
Intervention model
SINGLE_GROUP
Primary purpose
TREATMENT
Masking
NONE
Eligibility
Sex/Gender
ALL
Age
18 Years to 80 Years
Healthy volunteers
No
Inclusion criteria
1. Men and women, between 18 and 80 years, inclusive 2. Patients 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 movement disorder neurologist 4. Tremor refractory to adequate trials of at least two medications, one of which should be either propranolol or primidone. An adequate medication trial is defined as a therapeutic dose of each medication or the development of side effects as the medication dose is titrated. 5. Vim nucleus of thalamus can be target by the ExAblate device. The Vim region of the thalamus must be apparent on MRI such that targeting can be performed with either direct visualization or by measurement from a line connecting the anterior and posterior commissures of the brain. 6. Able to communicate sensations during the ExAblate MRgFUS treatment 7. 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. 8. Stable doses of all medications for 30 days prior to study entry and for the duration of the study. 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.
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Device or procedure related Adverse Events reported | 3 Months | Safety of the ExAblate transcranial treatment will be determined by an evaluation of the incidence and severity of device and procedure related complications from the first / treatment day visit through the 3-Months post-treatment time point. All AEs will be reported and categorized by investigators as definitely, probably, possibly, or unrelated to the device, procedure, or post-surgical changes in neurological status. Alternative treatments resulting from post-surgical changes in neurological status will be reported. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Tremor rating scales: the Clinical Rating Scale for Tremors | 3 Month | Primary effectiveness will be evaluated using validated, tremor rating scales: the Clinical Rating Scale for Tremors (CRST) for ET patients, based upon patients in whom unilateral ExAblate lesioning is attempted (i.e., Intent-to-Treat analysis). Efficacy is defined as a reduction in contralateral symptoms at 3-months post-treatment. |
Countries
South Korea
Outcome results
None listed