(photo credit: courtesy)
WASHINGTON, DC – In a presentation at the Congress of
Neurological Surgeons today, University of Virginia neurosurgeon W.
Jeffrey Elias, MD reported that preliminary results of a pilot clinical
trial indicate that MR-guided focused ultrasound has the potential to
safely and effectively control essential tremor (ET), a common
neurological condition that affects 10 million Americans.
Results from the study’s first 10 patients showed a 78 percent
improvement in contralateral tremor scores in the hand, as assessed with
the Clinical Rating Scale for Tremor (CRST). Patients’ functional
activities scores improved by 92 percent, as measured in the
‘Disability’ subsection of the CRST. Outcomes and complications were
comparable to other procedures for tremor, including stereotactic
thalamotomy and deep brain stimulation.
“So far, this noninvasive treatment has been life-changing for
patients,” said Elias, the study’s principal investigator and Director
of Stereotactic and Functional Neurosurgery at UVA. “All now have
improved ability to use their dominant hand to perform tasks that they
couldn’t do before treatment, such as writing legibly, drinking and
eating without spilling, and buttoning clothes. It has been exciting to
see their immediate improvements.”
The study is using magnetic resonance imaging to guide and monitor the
delivery of focused ultrasound to tremor-causing nerve cells in the
thalamus, a region deep within the brain known to be an effective target
for ET and other movement disorders. The treatment goal is to reduce
tremor in a patient’s dominant hand.
Most study participants have had ET for decades, Elias reported. As part
of the study’s inclusion criteria, all had previously taken at least
two medications that failed to control their tremor. Despite the
severity of their disability, patients had opted to cope with symptoms
rather than undergo invasive surgical procedures.
Conducted under an FDA-approved protocol, the single-arm,
non-randomized, phase 1 study began in February 2011 and is expected to
treat 15 patients before concluding. All patients are being followed for
three months. If final results prove successful, Elias anticipates
launching a larger, pivotal trial to study the overall safety and
long-term efficacy of MR-guided focused ultrasound in treating
Funding for the study is being provided by the Focused Ultrasound
Surgery Foundation, which is also underwriting a parallel study at the
University of Toronto in Canada. Foundation Chairman, Neal Kassell, MD,
says the study’s success could lead to other new treatments. “By
demonstrating that MR-guided focused ultrasound can treat tissue deep in
the brain with great precision and accuracy, we hope to open the door
to treating Parkinson's disease, epilepsy and brain tumors. Much work
remains to be done, but the path forward is clear,” he observed.
Kassell added, “Because the brain poses more complex technical
challenges than other organs, success in treating ET will spur
advancements in developing new focused ultrasound therapies for the
breast, liver, pancreas and prostate, which are less complicated to
Currently, MR-guided focused ultrasound is an FDA-approved therapy for
uterine fibroids; it is approved in Europe and elsewhere for the
treatment of uterine fibroids and pain associated with bone metastasis.
Around the world, clinical trials are treating prostate, breast, bone
and uterine tumors.