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Focused Ultrasound for Essential Tremor

Essential tremor (ET) may make it difficult to accomplish daily tasks and the activities you enjoy, but your symptoms shouldn’t take over your everyday well-being. In addition to medication, there are several ways you can treat your ET symptoms. One non-invasive method is focused ultrasound therapy, also known as focused ultrasound thalamotomy.

Here, we’ll discuss focused ultrasound therapy for essential tremor, how it works, the advantages and side effects, and more. Read on for a comprehensive overview, or use the links below to navigate throughout this post.


How Focused Ultrasound Therapy Works

Essential tremor symptoms can be treated using focused ultrasound, which targets and destroys a small region of brain tissue that causes the tremor. Because the process does not entail cutting into your body, healing is typically swift and painless for most individuals.

Focused ultrasound treatment for essential tremor works by combining magnetic resonance imaging and ultrasound technology:

  • Magnetic resonance imaging generates highly detailed pictures so that surgeons can carefully identify the area they need to target for treatment.
  • Ultrasound is a type of energy that can travel through many different tissues, including skin, fat, bone, and muscle. Highly focused ultrasound is the treatment that uses thousands of concentrated ultrasound beams to a targeted area of the body; in this case, the brain. As the ultrasound beams are applied to the targeted zone, the tissue’s temperature rises until it is ultimately destroyed. Note: the ultrasound beams only destroy the highly-targeted tissue, so surrounding tissue will not be affected.

Advantages of Ultrasound Therapy

Like any medical procedure or therapy, there are certain advantages and potentially negative side effects associated with ultrasound treatment for essential tremor. Below, we’ll take a closer look at these elements to consider as you evaluate a treatment plan with your physician.

Some of the advantages of guided ultrasound for essential tremor include:

  • Non-invasive, single treatment option that requires minimal recovery time
  • In most cases, patients may return to normal activity the following day
  • Focused ultrasound has a lower risk of infection, harm to the non-targeted area, and blood clot development than Radiofrequency Thalamotomy or Deep Brain Stimulation.
  • The procedure has the potential to offer rapid and effective results
  • Focused ultrasound does not expose the body to radiation
  • Focused ultrasound may be an alternative for medically refractory individuals (those who do not respond well to ET medicine) who do not want to have surgery because it is non-invasive.

Side Effects of Ultrasound Therapy

Focused ultrasound therapy may cause the following side effects in certain individuals:

  • Nausea
  • Headache during surgery
  • Temporary numbness and tingling in the fingertips or lips (mild to moderate)
  • Balance issues, temporary unsteadiness in walking
  • Temporary speech or swallowing issues

Note: Side effects may occur within several days or weeks after the procedure.

In addition to short-term side effects, focused ultrasound treatment may present the following long-term risks and complications:

  • Tremor may return months or years after the procedure
  • Tremor may not improve after treatment
  • About 10 to 15 percent of patients experience numbness or tingling in fingers or other parts of the body, muscle weakness, unsteadiness, sensory loss for several months after treatment, or permanently

What Conditions Can be Treated With Focused Ultrasound?

  • Essential tremor
  • Tremor-dominant Parkinson’s disease

The US Food and Drug Administration has approved MR-Guided focused ultrasound to treat symptoms associated with essential tremor as well as tremor-dominant Parkinson’s disease. While focused ultrasound may be used for both conditions, the two tremor disorders have some important differences to keep in mind when approaching treatment—read about Parkinson’s vs. essential tremor to learn more.

How Does Focused Ultrasound Reduce Tremors?

Focused ultrasound delivers targeted ultrasound energy to a part of the brain called the thalamus, which is associated with motor and sensory skills. As the ultrasound beams intensify, the tissue in the targeted area is destroyed and a tiny lesion will remain. The abnormal activity is interrupted by the little burn or lesion, which reduces the tremors associated with these disorders.

How is MR-guided Focused Ultrasound Performed?

The focused ultrasound surgery for essential tremor takes between 3-4 hours to complete. Here is a general outline of what to expect during the procedure:

  1. Your head will be shaved prior to the procedure to allow for better contact between the ultrasound and your brain.
  2. Your vital signs will be monitored and a catheter may be applied to drain your bladder during surgery.
  3. Your head will be positioned within a frame to keep it stable throughout the procedure.
  4. Medicine will be administered to increase your comfort.
  5. A silicone membrane will be positioned on top of your head to seal the space where cold water will circulate between your scalp and the helmet of the ultrasound device.
  6. You will lie on an MRI bed so that your physician can take several preliminary scans of your brain—this will help your surgeon identify the area they want to target in treatment.
  7. Before the procedure begins, you may be asked to complete several tasks so that your doctor may assess your tremor.
  8. The treatment will start with several low-frequency pulses of ultrasound to confirm the location for essential tremor.
  9. When the location is confirmed, the ultrasound energy levels will increase incrementally.
  10. As the procedure continues, you may be asked how you’re feeling and your medical team may instruct you to complete tasks, like drawing circles to evaluate your response to the treatment.
  11. The ultrasound energy is gradually increased as your tremor improves, until a tiny lesion forms.
  12. More MR images will be taken when your treatment is completed, and your urinary catheter, IV, and all head gear will be removed.

Note: You will be awake and able to communicate with your medical team throughout the entire procedure. During the focused ultrasound process, you will be given an emergency stop button to hold. You can press the button at any moment if you are having difficulty or are concerned about how you are feeling.

Following the focused ultrasound procedure, you’ll be taken to a recovery room to be monitored. You will have the option of returning home the same day or staying in the hospital for 24-48 hours. Your doctor will tell you when you are free to depart and when you must return for a follow-up appointment.

How Quickly Does One Experience the Results of Treatment?

Every individual is unique, and therefore, response to treatment can vary. According to the Cleveland Clinic, patients should notice improvements during the procedure.

What Are The Long-Term Results of This Treatment?

Guided ultrasound for essential tremor has proven to be quite effective for ET and tremor-dominant Parkinson’s disease.

During a trial on individuals with essential tremor, patients reported a 50% improvement in their tremors and motor functions 3 months after focused ultrasound therapy, leading to FDA approval, and a 40% improvement one year later.

When studied on individuals with tremor-dominant Parkinson’s, patients in the FDA-approved trial experienced a 62% improvement in their hand tremor three months following focused ultrasound therapy.

Cala Trio Can Help

Essential tremor treatment is a long road for many. Some individuals find an effective medication or therapy right away, while others have to get creative with the help of their physician. Cala Trio’s groundbreaking technology is designed to work with your unique tremor and treatment goals. To learn more about our essential tremor bracelet, visit the Cala Trio therapy FAQ page.