Transcranial MR-Guided Focused Ultrasound

Transcranial MR-guided focused ultrasound is a noninvasive, image-guided treatment that is performed as an outpatient procedure. It is Food and Drug Administration (FDA)-approved for treating essential tremor (ET) and tremor-predominant Parkinson’s disease (TPPD).

UT Southwestern is the first medical center in Texas to offer the procedure.

Peter O'Donnell Jr. Brain Institute

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Transcranial MR-guided focused ultrasound, also called transcranial MR-guided high-intensity focused ultrasound (MRgHIFU), uses high-intensity ultrasound waves to interrupt brain pathways that conduct the signal that causes a tremor. It works by focusing ultrasound waves into the brain, heating tissue with very precise control – without making any incisions in the skull.

Benefits of Transcranial MR-Guided Focused Ultrasound

No incisions
No anesthesia
No implantable device
Reduced adverse effects
Improved results

Conditions We Treat Using Transcranial MR-Guided Focused Ultrasound

Transcranial MR-guided focused ultrasound is used to treat a variety of neurological conditions. The FDA has approved its use for:

Essential tremor
Tremor-dominant Parkinson’s disease

'It's Amazing the Difference It Made'

Jimmy Hiner struggled for decades with a tremor in his right hand that affected his ability to function. After being diagnosed by experts at the O'Donnell Brain Institute, he became the first patient in Texas to undergo a procedure called high-intensity focused ultrasound (HIFU), which uses MRI-guided ultrasound waves to precisely target an area in the brain linked to Parkinson’s disease and essential tremor.

What to Expect

Patients with tremor who are interested in this approach are evaluated by a neurologist specializing in movement disorders.

The evaluation includes a complete medical history and physical. There are many potential causes of tremor, so the first step is accurate diagnosis. We then review all options for bringing the tremor under control, including pharmacological therapy, brain surgical treatments, and transcranial MR-guided focused ultrasound.

Patients who are possible candidates for either deep brain stimulation surgery or transcranial MR-guided focused ultrasound are enrolled in UTSW’s neuromodulation network. The network organizes a series of tests, including measurement of tremor severity using validated scales and videotape analysis, cognitive testing, and other tests as needed. After the testing, we hold a multidisciplinary conference with neurologists, neurosurgeons, neuroradiologists, neuropsychologists, and physical therapists to review each patient’s case. We recommend the best option for the patient, considering the risks and benefits of each approach and the patient’s preference. If transcranial MR-guided focused ultrasound is recommended, patients then meet with neuroradiologist Bhavya R. Shah, M.D., an expert in MRgHIFU.

Before the procedure

Dr. Shah reviews the patient’s medical records with them. The patient then has a computed tomography (CT) scan of their head to determine their skull density ratio (SDR), which will determine whether the patient is a candidate for the procedure.

The patient also receives a special advanced brain magnetic resonance image (MRI) scan that allows Dr. Shah to map the brain.

Day of the procedure

Dr. Shah and a movement disorders neurologist meet the patient. After a brief neurologic exam, the patient is taken to the Neuro MRgHIFU suite in Clements University Hospital. A plastic frame is attached to the patient’s head to prevent motion during the procedure. The patient is then placed in the MRI scanner for treatment.

During the treatment, the patient may experience nausea or have a falling sensation. Antinausea medicine is given prior to the procedure to help alleviate these feelings. The patient spends 45-60 minutes in the MRI scanner for the treatment and is evaluated after each ultrasound therapy has been delivered to ensure that the tremor is improving and side effects are not occurring.

Once the target is confirmed, higher-energy ultrasound waves are delivered. When this is finished, the procedure is complete, and the head frame is removed.

A follow-up MRI exam is performed, and then the patient is taken to a recovery area for two hours. After recovery, the patient is discharged from the hospital with instructions to follow up with Dr. Shah in two days.

After the procedure

In the initial hours following the procedure, the patient might experience a mild headache. Because there are no incisions or anesthesia, there is no prolonged recovery period, but we recommend that the patient take it easy for the next two weeks.

The patient should follow up with the referring neurologist for ongoing management and medication adjustment, if needed. If the tremor recurs or is incompletely controlled following transcranial MR-guided focused ultrasound, the patient might be a candidate for re-treatment using the same technology or with alternative approaches.

“Transcranial MR-guided focused ultrasound offers us another valuable tool to help patients with tremors.”

Bhavya R. Shah, M.D.
Assistant Professor of Radiology

Transcranial MR-Guided Focused Ultrasound Clinical Trials

Dr. Shah is also pursuing research into using MR-guided focused ultrasound to help deliver drug therapies and diagnostic agents into the brain – past the blood-brain barrier, an immunological defense that prevents material in the blood from entering the brain. The research is investigating diagnosis and treatment of neurodegenerative diseases such as Alzheimer’s disease, brain tumors, and other diseases of the brain.