Focused ultrasound treatment for essential tremor has been approved by the Food and Drug Administration (FDA) in July 2016.
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 completely non-invasive method of thalamotomy - a procedure in which a predefined small volume of brain tissue containing nerve cells causing the tremor is destroyed - that could be an effective option for certain patients. It is performed while the patient is awake and involves no anesthesia, no incisions in the scalp, and no burr holes through the skull or insertion of electrodes into the brain.
Most clinical studies target a region in the thalamus involving the Vim nucleus and were performed on only one side of the brain. Recent studies from Switzerland demonstrated safety and efficacy in targeting a different part of the thalamus called the cerebellothalamic tract (CTT), below the thalamus. To learn more about the CTT approach see the Center for Ultrasound Functional Neurosurgery Solothurn website.
Focused ultrasound may offer the following benefits in treating ET:
- It is a non-invasive, 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 Ohio State University is looking at pre-targeting images to see if this can help in long term sustainability of ET treatments.
A clinical trial in the UK 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, Medicare, at a national level, allows payment, of approximately and most regional payment centers for Medicare are covering this procedure. However, there are still a few regions that are not, so patients should inquire from their physician regarding payment.
Although the code for this care (0398T) has been approved to move to the payable class, it will not transition to the updated codes until late 2019. Until then, it is more likely that payment rejections will have to be appealed in order to ensure payment.
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.
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