MRgFUS Thalamotomy Offers Durable Tremor Control

“The most intense conflicts, if overcome, leave behind a sense of security and calm that is not easily disturbed.”
-Carl Jung

Carl Jung, a pioneer in analytic psychology, recognized the paradox of dealing with inner turmoil and vanquishing it as a path to lasting peace. While we may wish that life was simpler and trouble-free, the fact of wrestling with inward pain and eventually overcoming it is deeply satisfying. It feels good and leaves a lasting positive imprint on how we view ourselves.

Living with essential tremor (ET) is not just a physically disabling. It brings inner struggles as well. It is a challenge to maintain self-confidence and optimism in the face of embarrassment. It is hard to decide to socialize when isolation is all too tempting. It can feel defeating to be turned down for a job because tremors were misperceived as nervousness, or to fear losing one’s job when tremors interfere with work responsibilities. Compounding all this, no matter how much determination one has, ET becomes a foe that all the will power in the world can’t control. It takes courage and patience to try to overcome each day’s challenges. When will it end and bring a return to a serene life?

Medication is not a permanent solution for many

When a person receives a diagnosis of ET, the first line of treatment is usually one of two categories of medication: either beta-blocker such as propranolol, or an anticonvulsant (antiseizure) drug such as primidone. According to a 2017 article on Medscape:

The drug is introduced at a low dose that is increased slowly until complete response, tolerance, or usual maximum dose is attained. If some benefit is achieved but is incomplete, the other medication may be introduced and increased in an effort to achieve maximum benefit. Treatment with both drugs has been shown to be effective in patients who have had an insufficient response to one. Patients should not expect complete resolution of symptoms.

In fact, medication appears to offer long-term help in only about 50% of people with ET, and there may be an added cost in terms of side effects and gradually increasing doses. “Maximum benefit” will differ from one person to another, since ET is now recognized as a family of brain abnormalities; in most cases, the tremors do not completely disappear, but a reduction is better than no help at all. Still, it’s hard to face the prospect of tremor progression to a point where no drug will be effective.

A durable treatment with no medication

A new noninvasive, outpatient neurosurgery called MRI-guided Focused Ultrasound thalamotomy (MRgFUS thalamotomy) offers the promise of lasting results. While it was only recently approved (July, 2016) to treat ET, over 1000 people worldwide have been treated with thousands more expressing avid interest. What makes it so appealing is that within a matter of hours, ultrasound energy beamed through the skull (no incision, no holes drilled) targets a very small center in the brain’s thalamus, where it permanently destroys a tiny part of what is called the tremor pathway. As a result, the abnormal signals can go no further, and tremors in the dominant hand are stopped without causing damage to other brain areas.

Since MRgFUS thalamotomy is so new, there is no way to calculate what the 5- or 10-year results will be, but so far, they are very promising. For instance, a 2018 international, multi-center study followed patients for 2 years to evaluate durability. The medical centers involved covered territory from Asia (Japan and Korea) to Canada and coast-to-coast cities in the U.S.

Initially, 76 patients were treated in the original randomized study of MRgFUS thalamotomy on the side of the brain that controlled the dominant hand. Each had moderate-to-severe ET that had shown no response to at least two attempts with medication. For the durability study, 67 of the original treated participants continued during the follow-up study. A clinical rating scale for tremor was used to assess the reduction in tremor and measure how long it lasted over the two-year period.

Keep in mind that during the randomized treatment trial, the doctors were initially somewhat on the cautious side in terms of how much power they were delivering to the target, so some of the later patients benefited from a more thorough effect as confidence grew. Therefore, tremor control was not even across all patients. At 6 months after treatment, there was an average improvement in disability of 64%. However, what is noteworthy is that this improvement was sustained at 1 year and 2 years.

The authors concluded, “Tremor suppression after MRgFUS thalamotomy for ET is stably maintained at 2 years. Latent or delayed complications do not develop after treatment.”

As with every new procedure, there is a learning curve, and MRgFUS thalamotomy continues to improve as one might expect. Of course, there is no crystal ball to predict if these changes are truly permanent. For now, patients who undergo this treatment are practically jubilant to end the struggles and inner conflicts that accompany ET—and to get rid of the pills and other remedies they tried during the years of combatting their disabilities. Most importantly, they look forward to “a sense of security and calm that is not easily disturbed.” For more information on MRgFUS thalamotomy, contact Sperling Neurosurgery Associates.

i. Chang JW, Park CK, Lipsman N, Schwartz ML, et al. A prospective trial of magnetic resonance-guided focused ultrasound thalamotomy for essential tremor: Results at the 2-year follow-up. Ann Neurol. 2018 Jan;83(1):107-114. doi: 10.1002/ana.25126.