A noninvasive alternative for selected Parkinson’s patients
Magnetic resonance-guided focused ultrasound, or MRgFUS, is emerging as a treatment option for some people with Parkinson’s disease whose motor symptoms remain difficult to manage. The outpatient procedure uses focused ultrasound waves, guided by magnetic resonance imaging, to create a precise lesion in a small pathway deep in the brain.
The goal is to interrupt abnormal movement signals associated with disabling symptoms such as tremor, stiffness, slowed movement and involuntary movements known as dyskinesia. It does not cure Parkinson’s disease, but clinicians say it can improve quality of life by reducing some of its most disruptive motor effects.
Parkinson’s disease affects about one million people in the United States. Medication is widely used to manage symptoms, but its benefit may be incomplete for some patients, and treatment decisions can become more complicated as symptoms progress.
How MRI-guided focused ultrasound works
Unlike deep brain stimulation, MRgFUS does not require electrodes to be implanted in the brain. During the procedure, ultrasound beams are directed through the skull toward a carefully selected target. MRI is used to guide the treatment and monitor the target area.
The patient’s head is shaved to help ultrasound energy pass efficiently through the scalp, and the patient wears a helmet while lying in an MRI machine. The helmet focuses the beams on the intended pathway in the brain. At that location, the energy is used to make a controlled, precise lesion intended to interrupt abnormal signaling.
This combination of imaging and focused energy distinguishes the approach from conventional surgery. There is no implanted stimulation system, and the procedure is designed to be performed without an incision into the brain. That difference can be important for patients who do not want, or are not suited to, an implanted-device approach.
Deep brain stimulation remains a different path
Deep brain stimulation is another established treatment strategy for Parkinson’s motor symptoms. It involves surgically implanting electrodes in brain structures involved in movement control. Those electrodes are used to influence the relevant neural activity.
For some patients, however, the prospect of brain surgery is a major barrier. The focused-ultrasound approach offers a different risk-and-benefit profile because it is noninvasive and does not depend on implanted electrodes. It is not simply a replacement for every patient who might be considered for deep brain stimulation; treatment selection still depends on the individual’s symptoms, treatment history and clinical assessment.
At Weill Cornell Medicine and NewYork-Presbyterian/Weill Cornell Medical Center, neurologist Harini Sarva recommended MRgFUS through a clinical-trial pathway for patient Stan Au, who had experienced increasingly difficult tremor and other motor symptoms despite taking commonly used medication. His experience illustrates the clinical need for additional options, particularly when daily tasks become hard to perform.
Targeting symptoms rather than curing disease
Focused ultrasound is intended to relieve particular motor symptoms, not reverse the underlying disease. Parkinson’s can affect movement in multiple ways, including rigidity, slow movement, tremor and dyskinesia. A procedure that interrupts an abnormal movement pathway may help with selected disabling effects, while other aspects of the disease can remain.
That distinction matters for patients and families evaluating reports of new treatments. The promise described by clinicians is better symptom control and improved day-to-day function, rather than a cure. Careful discussions with a movement-disorders specialist are needed to determine whether a particular symptom pattern and medical history make a person an appropriate candidate.
The treatment also shows how imaging is becoming part of intervention, not only diagnosis. MRI provides the setting in which the ultrasound target can be selected and treated, allowing clinicians to focus energy deep in the brain without placing an electrode there.
What the approach could mean
For patients living with symptoms that interfere with eating, writing, recreation and other routine activities, a noninvasive option can be consequential. The procedure may be particularly meaningful for people reluctant to undergo an operation involving implanted hardware.
Its role should still be understood in context. Parkinson’s is a complex condition with no cure, and focused ultrasound is not presented as a universal answer to every motor symptom or every stage of disease. It is one tool in a broader care plan that can include medication, specialist follow-up and, for some people, surgical or device-based treatment.
Even so, the availability of a targeted outpatient procedure expands the treatment conversation. By using MRI guidance and ultrasound energy to alter a small movement-related pathway, MRgFUS offers a way to address certain severe symptoms while avoiding implanted electrodes and open brain surgery.
This article is based on reporting by Medical Xpress. Read the original article.
Originally published on medicalxpress.com
