Focused ultrasound treatment for essential tremor has been approved by the Food and Drug Administration (FDA) in July 2016. Medicare approved the treatment in all US states as of July 12, 2020.
Essential tremor (ET) is the most common movement disorder, affecting an estimated 3% of the population, or approximately 10 million individuals in the United States. ET is commonly viewed as a relatively benign disease.
However, the associated disabling aspects of ET, such as significant tremor of the hands, can impair patients’ ability to eat, shave, write, perform household activities, and function in the workplace.
The underlying etiology of ET is unclear, but cases often run in families (familial tremor). It has been estimated that approximately 50% of all cases are due to a genetic mutation, and the pattern of inheritance is most consistent with autosomal dominant transmission (i.e. dominant trait).
Focused Ultrasound Therapy
Focused ultrasound is a noninvasive, therapeutic technology with the potential to improve the quality of life and decrease the cost of care for patients with essential tremor. This novel technology focuses multiple beams of ultrasound energy precisely and accurately on targets deep in the brain without damaging surrounding normal tissue.
How it Works
Where the focused ultrasound beams converge, they produce precise ablation (thermal destruction of tissue), enabling ET to be treated noninvasively. The primary target is a region in the thalamus called the ventral intermediate nucleus (Vim), but other adjacent targets and white matter pathways are also in use.
Current treatments are being performed on one side of the brain, but there is a study underway of staged bilateral treatments.
- It is a noninvasive, single treatment that enables patients to recover rapidly and quickly return to activities of normal life (usually the next day).
- Compared to RF ablation or DBS, focused ultrasound offers a reduced risk of infection, of damage to the non-targeted area, and of blood clot formation.
- Focused ultrasound offers rapid resolution of symptoms.
- In contrast to lesioning performed with stereotactic radiosurgery, focused ultrasound does not use ionizing radiation, thus avoiding the side effects of exposure to radiation.
- Because it is non-invasive, focused ultrasound could be an option for medically refractory ET patients (those who do not respond well to medication) who do not want to undergo surgery.
Phase 3 Pivotal Clinical Study
Enrollment has been completed in a multi-center pivotal randomized study to evaluate the safety and efficacy of focused ultrasound for the treatment of medication-refractory essential tremor patients. Results of this study have been reviewed and approved by the FDA.
A clinical trial at the University of Maryland is doing staged bilateral treatments for ET. The interval between treatments will be at least nine months.
A clinical trial in the UK and Spain has begun and is doing staged bilateral treatments. This group will treat the second side after at least nine months have passed after the first treatment.
Please see a list of possible treatment sites here.
Regulatory & Reimbursement
The Exablate system manufactured by Insightec earned FDA approval to treat essential tremor in July 2016. It is also approved for treating essential tremor in Europe, Korea, Canada, Japan, Russia, Taiwan, and the Middle East.
In the US, the Medicare contractors in the various states incrementally approved focused ultrasound treatment for essential tremor. However, on July 12, 2020, all US sites approved for payment under Medicare.
Commercial coverage and Medicaid will typically follow Medicare but should be evaluated with each company and region. Some facilities have a cash payment option, for those who are not willing to wait for insurance decisions for payment. Prices vary, but a rough estimate is $40,000.
Device manufacturer, Insightec has established an informational website, including patient stories and access to treatment site information. They have also set up a Reimbursement Support Manager, who can help with questions about the status of reimbursements. Her contact information is: Kim Martin, Reimbursement Support Manager, 1-(866) 392-8478 or .
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Click here for additional references from PubMed.
Pre- and post-treatment assessment videos courtesy of University of Virginia