Washington — If “brain tsunamis” can be prevented, it may be possible to keep some patients who have sustained a serious head injury from suffering devastating further damage to the brain, according to a new study.
Jed Hartings PhD
That study, published recently in Lancet Neurology, suggests that cortical spreading depolarizations, also called brain tsunamis, are independently associated with worsening outcomes after a severe head injury. The study was funded mostly by a four-year $1.96 million grant from DoD, and its results could be important for treatment of traumatic brain injury (TBI) in the military.
“If we can intervene and stop these from occurring, potentially, we can save more functional brain tissue in patients who have experienced TBI, and they will go on to a better recovery,” principal investigator Jed Hartings, PhD, assistant professor in the department of neurosurgery at the University of Cincinnati (UC) told U.S. Medicine.
Researchers discovered that, of 103 civilian patients undergoing neurosurgery following a serious head trauma, 58 experienced a phenomenon called cortical spreading depolarizations.
Hartings said that during a brain tsunami, electrical function is lost in the brain cells in a manner that is worse than a seizure. He compared this to a battery discharging.
“What happens during spreading depolarization is that this polarization is lost. The battery discharges in the cell, and the cell basically becomes a swollen sack of salt water without any capacity to generate electrical signals. Of course, maintaining electrical polarization is essential to the viability of brain cells. When that is lost, cells have to work very hard to pump ions out of the brain into the surrounding fluid to restore the normal electrical charge and function,” he said.
What he said was most surprising about the study results was the extent of brain tsunami activity measured in some of the brains. A total of 1,328 spreading depolarizations were measured in the 58 patients.
“Ten years ago, everyone thought that spreading depolarizations were something you only observed in lower species with different brain architecture and that it wouldn’t exist in the human brain, with its complex gyrations and complex architecture. So the fact that we are seeing this in human disease and we can record these events happening continuously for several days, numbering in the hundreds of events — it is absolutely astounding.”
An Army researcher agreed that the study had advanced knowledge of TBI.
“We have no therapeutics for treating a brain injury. … We desperately need one, and it is studies like this that give you hope that we will be successful,” said Frank Tortella, PhD, chief of the Brain Trauma Neuroprotection & Neurorestoration Branch and the Combat Casualty Care Research Program Brain Trauma Program Manager in the Center of Excellence for Psychiatry & Neuroscience at the Walter Reed Army Institute of Research in Bethesda, MD.
Tortella told U.S. Medicine that, while the patients in this study were from civilian centers, this research is “highly relevant to brain injury, whether it is military or civilian.”
All of the participants in the study had a severe TBI, and most of the patients were in a coma. One of the limitations of the study is that monitoring spreading depolarizations requires placement of an electrode strip on the brain’s surface, restricting the study population to patients undergoing craniotomy. This raises the question of “generalizability of our findings to a non-surgical population,” the researchers wrote.
“A noninvasive method for monitoring of spreading depolarizations would accelerate efforts to validate these findings and investigate their application,” the researchers wrote.
Most of the patients in the study were treated at King’s College Hospital in London, but nine were treated at UC Health University Hospital. Other participants in the international study were at the University of Miami, the University of Pittsburgh, Virginia Commonwealth University and the German centers Charité University Medicine in Berlin and University Hospital in Heidelberg. The collaborating scientists and clinicians are members of the Co-Operative Studies of Brain Injury Depolarizations.
“This study provides real, concrete evidence that brain tsunamis can cause further damage to the brain in the few days after a major injury,” according to Anthony Strong, emeritus professor of neurosurgery and a former neurosurgeon at King’s College Hospital, who led the study in Great Britain.
“This is significant, because they have a direct link to poor recovery in patients. Of course, the end goal is to take the results of this study and, longer term, develop new treatments for this type of injury,” Strong said in a press release about the study. “This potentially may mean finding a way of blocking these killer waves as they are happening.”