Key Points
- Data from a 10-patient pilot clinical trial using focused ultrasound to treat cervical dystonia were recently published.
- Cervical dystonia is a rare neurological disorder that causes uncontrollable neck muscle contractions.
Focused Ultrasound Pallidothalamic Tractotomy in Cervical Dystonia: A Pilot Study
Final data from a pilot clinical trial in Tokyo, Japan, were recently published in the journal Movement Disorders. Shiro Horisawa, MD, a neurosurgeon at Tokyo Women’s Medical University, led the 10-patient trial (Japan Registry of Clinical Trials Number 032210506). The study evaluated the safety and initial effectiveness of using Insightec’s Exablate Neuro focused ultrasound device to create a pallidothalamic tractotomy, or brain lesion, in patients with a rare condition of the neck called cervical dystonia.
People with cervical dystonia can experience uncontrollable neck muscle contractions, and the condition is also known as spasmodic torticollis. It is rare neurological disorder that is caused by faulty neurons in the brain. According to the National Organization for Rare Disorders, “In some cases, these abnormal contractions may be sustained or continuous; in others, they may be present as spasms that can resemble tremor. The severity of cervical dystonia can vary, but the disorder can cause significant pain and discomfort as well as difficulty due to the abnormal postures. It can affect quality of life and activities of daily living including employment.”
Six men and four women between the ages of 41 and 61 years were enrolled in the study. They were assessed with the Toronto Western Spasmodic Torticollis Rating Scale (TWSTRS) at baseline and again six months after undergoing the focused ultrasound procedure. The TWSTRS score improved 43.4% from baseline to six months after treatment, and this improvement was significant (P < 0.001). Another significant improvement was measured in the Burke-Fahn-Marsden Dystonia Rating Scale, which improved by 38.2% (P < 0.001) from baseline. The Beck Depression Inventory, Beck Anxiety Inventory, and Apathy Evaluating Scale all improved as well. Some adverse effects were found, including reduced hand dexterity in three participants and weight gain in two of them.
The authors concluded that focused ultrasound pallidothalamic tractotomy may be an effective treatment option for patients with cervical dystonia. The publication also mentions that “Unilateral surgical treatment may be insufficient as a treatment for cervical dystonia,” noting that the treatment may need to be done bilaterally instead of only on one side, as is typically done with successful deep brain stimulation treatments.
“This is the first clinical trial of focused ultrasound surgery for cervical dystonia,” said Dr. Horisawa. “The participants showed significant improvements in their TWSTRS scores; however, we did find a wide range of individual responses. My next step is to investigate how focused ultrasound can address cases where the improvement from this treatment was insufficient. This includes exploring the potential for bilateral treatment and identifying the optimal parameters for selecting suitable patients. I am committed to continuing my research to solve these challenges and to improve the lives of dystonia patients worldwide.”
“The treatment of patients with Parkinson’s disease also produced some improvement in their dystonia, which prompted the expansion of this work to treat patients with other types of dystonia,” said Tim Meakem, MD, a managing director of the Foundation and co-director of the Research and Education Team. “We are thankful for Dr. Horisawa’s research and look forward to further refinements and expansions of this innovative technology.”
The Foundation funded this clinical trial, the first in the world use of focused ultrasound for treating cervical dystonia.
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