Scientists have proven that previous success in reviving a patient's consciousness using ultrasound was not a fluke. Two more people previously trapped in long-term “minimally responsive states” have had some awareness of the world restored, at least temporarily.
In 2016, a team at UCLA announced they had focused ultrasound pulses at a frequency of 650 kilohertz on the thalamus, an area deep inside the brain usually considered to contain the master-switch of consciousness. By the next day the patient had made dramatic improvements, and within a week was communicating, bumping fists with doctors, and attempting to walk. The 25-year-old man, initially in a coma after an accident, and had only shown limited pre-treatment recovery.
Unlikely as it seems that such a dramatic change of fortunes could be a coincidence, the team, led by Professor Martin Monti, urged caution until wider testing could occur. They have now treated three more patients who had shown little to no response to stimulation, achieving encouraging progress in two.
A 56-year-old stroke survivor who had been unable to communicate for 14 months grasped a ball and dropped it on command after two rounds of treatment, Monti and colleagues report in the journal Brain Stimulation. He could also shake or nod his head to give the correct response to basic questions, and respond to hearing a relative's name by looking at their photograph, rather than an alternative. He even temporarily developed the capacity to bring a bottle to his mouth and to put a pen to paper.
Unfortunately, echoing the film Awakenings and the events on which it was based, by the three-month mark after treatment he had regressed to his original state.
A woman whose heart attack had left her showing almost no signs of consciousness for 2.5 years became able to recognize household objects after a single round of treatment. Her level of consciousness varied in follow-up assessments but was always above her pre-treatment state.
Tripling your successes would be big for anyone, but Monti said in a statement, “I consider this new result much more significant because these chronic patients were much less likely to recover spontaneously than the acute patient we treated in 2016.” Other techniques sometimes manage to restore consciousness to patients in vegetative or minimally conscious states, but the paper notes successes for those with chronic versions of these conditions are rare.
Moreover, Monti noted: “Any recovery typically occurs slowly over several months and more typically years, not over days and weeks, as we show.”
Patients were treated with 10 bursts of 30-second ultrasound, interrupted by 30 seconds without stimulation, repeated a week later. Measurements like blood pressure and oxygen levels were unaffected. Monti intends to create portable ultrasound devices capable of applying the stimulation in patients' homes but stresses it will take years before safety is confirmed enough for widespread application.
Despite the heartbreak of regression, Monti recounted the first patient's wife saying, “'This is the first conversation I had with him since the accident.'”
“For these patients, the smallest step can be very meaningful – for them and their families,” Monti said. “To them, it means the world.”