Researchers at the University of California, Los Angeles are continuing to find success using ultrasound to “jump-start” the brains of people stuck in a minimally conscious state. In a report out this month, they detail two patients with chronic and severe brain injuries who experienced improvements in their awareness of the outside world after undergoing the treatment. The scientists are now more hopeful about the future of ultrasound for these difficult cases.
In 2016, California resident Bradley Crehan was struck by a car, which caused a severe brain injury. Following surgery, Crehan was put in a medically induced coma to help him recover. But Crehan showed few signs of awareness after being woken up and was largely unable to communicate with others. He was then given an experimental treatment called low-intensity focused ultrasound (LIFU) by scientists at UCLA.
The treatment involved pulses of ultrasound directed to the brain’s thalamus — a region that helps us coordinate our motor and sensory functions and one that’s thought to play a key role in consciousness — for five minutes, in hopes of awakening activity that tends to go dormant during coma. A day after the treatment, Crehan began to show signs of recovery and was able to recognise and reach for objects. Days later, he was able to respond to questions through blinking. And within four months, sooner than doctors had predicted, he was fully conscious and able to leave the hospital, though he would still require ongoing physical therapy and rehabilitation.
As amazing as Crehan’s recovery was, it’s of course possible that the ultrasound therapy wasn’t the cause. People spontaneously recovering from a coma-like state isn’t unheard of, especially in the first days and weeks after it’s begun. It was possible the technique was simply a red herring and that Crehan would have woken up no matter what doctors did.
In the new report, published this month in the journal Brain Stimulation, the authors say they now have more evidence that ultrasound really can help people teetering on the edge of consciousness.
They used the technique on three patients living with chronic brain injuries that had left them in a minimally conscious state for more than a year. In one patient, the ultrasound didn’t seem to improve their function at all. But in the other two, doctors saw an improvement within days of the first of two treatments. One patient — a 56-year-old man who had suffered a stroke — was able to respond to certain commands, answer yes-or-no questions, and recognise family members in a photo. The other — a 50-year-old woman who suffered cardiac arrest — could now recognise objects and communicate with others.
“What is remarkable is that both exhibited meaningful responses within just a few days of the intervention,” said study author and UCLA psychologist Martin Monti in a statement released by the university. “This is what we hoped for, but it is stunning to see it with your own eyes. Seeing two of our three patients who had been in a chronic condition improve very significantly within days of the treatment is an extremely promising result.”
Because chronic coma-like patients are much less likely to spontaneously recover than acutely comatose patients, the researchers are more confident that ultrasound made the difference here. Importantly, there were also no safety concerns noticed, with patients’ vital signs staying level throughout the treatment.
Unfortunately, the treatment of these patients didn’t lead to the same amazing recovery that Crehan experienced. The 50-year-old woman did continue to have improved awareness months later, but she was still considered to be minimally conscious, while the 56-year-old man’s condition regressed to his baseline by the time of a follow-up visit three months later. It’s likely that restoring people to consciousness will remain a difficult and impossible task in many cases, even if this technique does prove to work.
Still, for the families of these patients, even some level of regained awareness will be worthwhile, and there may yet be ways to improve the effectiveness of this and similar brain stimulation techniques being studied. For now, the UCLA scientists are continuing their research with ultrasound and hope to soon pursue clinical trials with a larger group of patients. They also plan to study exactly how this technique is altering the brain.