Brenda Hric consults with neurosurgeon Dr. Jeff Elias, who conducted her focused ultrasound.
CNN  — 

Undergoing clinical trials around the world is a brain surgery that doesn’t need an incision or produce any blood yet drastically improves the lives of people with essential tremor, depression and more. The procedure, known as a focused ultrasound, aims sound waves at parts of the brain to disrupt faulty brain circuits causing symptoms.

“Focused ultrasound is a noninvasive therapeutic technology,” said Dr. Neal Kassell, founder and chairman of the Focused Ultrasound Foundation. “We’ve said that focused ultrasound is the most powerful sound you will never hear, but sound that someday could save your life.”

Kassell describes the way it works as “analogous to using a magnifying glass to focus beams of light on a point and burn a hole in a leaf.”

“With focused ultrasound, instead of using an optical lens to focus beams of light,” he added, “an acoustic lens is used to focus multiple beams of ultrasound energy on targets deep in the body with a high degree of precision and accuracy, sparing the adjacent normal tissue.”

Kassell served on the board of Insightec — a leading maker of focused ultrasound machines — more than 10 years ago, according to an Insightec spokesperson. As a result, he holds .03% of the company’s private shares. Kassell told CNN the financial aspect doesn’t drive his interest in focused ultrasound procedures.

screengrab gupta holding brain
A look at the brain like you've never seen it before
03:13 - Source: CNN

The procedure has been significantly beneficial for people with essential tremor, a neurological disorder that causes involuntary and rhythmic shaking. The disorder can affect almost any body part, but the tremors typically occur in hands — even during simple tasks such as eating, drinking or writing.

Essential tremor is usually more prominent on one side of the body and can worsen with movement. It’s most common in people 40 and older, and it affects nearly 25 million worldwide, according to a 2021 study.

Such was the case with Brenda Hric, 80, who recently underwent focused ultrasound at the University of Virginia, a pioneering institution of the procedure.

Hric’s tremors made her uncomfortable in social situations because she was afraid of spilling or knocking something over, she told CNN.

But just 44 seconds of focused ultrasound waves got rid of her tremor.

“I looked at my hand, and I could see that it was not moving, and that was the first time I had been able to see my fingers still in about 20 years,” Hric said. “I think it’s definitely a miracle, and I thank the Lord for it.”

How it works

Focused ultrasound is a form of functional neurosurgery, the targeting of precise structures deep in the brain to change it, to restore function or, in this case, to stop a tremor. It’s an alternative treatment for those who, like Hric, don’t respond to or stop being affected by conventional medication treatment, experts said.

“In a simplistic sense, you can imagine that there’s a bunch of abnormal neurons in this one target that are firing away uncontrollably, causing the tremor, the shaking,” Kassell said.

Focused ultrasound technology uses a transducer to force beams of sound waves to converge at one point to raise the temperature and destroy tissue.

Before receiving high-intensity focused ultrasound, the one necessary for treating essential tremor, patients need to have their heads shaved since air can sometimes get trapped in hair follicles.

The patient then undergoes MRI and CT scans so doctors can use the resulting images to map the structure of the brain and the target.

Pictured are scans of Hric's brain. Focused ultrasound signficantly improved the 80-year-old's tremors.

The Insightec Exablate Neuro, a focused ultrasound platform, instructs how many beams should be used to do the treatment, then neurosurgeons might do what Dr. Jeff Elias calls “test shots, just to make sure we’re focused right at the bull’s-eye.”

A UVA Health neurosurgeon who treated Hric, Elias is a pioneer of treating essential tremors using ultrasound waves. In 2011, he led the clinical trials critical for gaining regulatory approval of this procedure in the United States.

“These (test shots) are really low energy, but we want to see if our treatment is exactly where we want it,” he said. “This is our chance to kind of sight the rifle.”

Four 11-second treatment doses significantly improved Hric’s tremor. The entire procedure lasted less than two hours, with most of it spent mapping the brain and testing the target.

Beforehand, Hric had trouble drawing inside the lines of circles. Focused ultrasound helped her color inside the lines.

Pros and cons

Generally, anyone with an essential tremor diagnosis not responding to medications would be eligible for focused ultrasound treatment, said Dr. Nir Lipsman, a scientist at Sunnybrook Health Sciences Centre in Toronto and director of Sunnybrook’s Harquail Centre for Neuromodulation.

People who can’t undergo MRI scans due to claustrophobia or having metal inside their body aren’t eligible for focused ultrasound, said Dr. Noah Philip, a professor of psychiatry and human behavior at Brown University’s Alpert Medical School. Philip is also lead for mental health research at the VA RR&D Center for Neurorestoration and Neurotechnology.

Ideally, the benefits of focused ultrasound are permanent, Lipsman said. “If you’re able to destroy the part of the brain responsible for the tremor, it should be a permanent effect,” he said. “At one year, however, some of these patients will have a rebound or recurrence of their tremor, and we don’t know why that is.”