|Source: Pexels Creative Commons|
Mary at 9 months old underwent gastrointestinal (GI) surgery. At the recovery room, her mom, Beth suspected something wasn’t quite right. Her little girl’s eyes were “pulsing” strangely. She called the nurse’s attention who dismissed the “pulsing” as “normal pain response” after surgery. A few hours passed when Mary’s eyes trembled again and frequently too. The nurse tried to abate Beth’s fears with shots of morphine in Mary’s drip. But the little girl suffered from profound and rapid brain death and her “pulsing” were actually seizures. Mary was in a coma and died shortly after.
The “Brain Stethoscope”
Neurologists at Stanford Neurosciences Institute and Child Health Research Institute have devised a “brain stethoscope” for cases like Mary’s. This breakthrough device can change the fates of millions of Marys and the Epilepsia landscape today by converting brainwaves into sounds. The brain stethoscope was developed for years with a computer music expert who designed the algorithm that converts the electrical activity in the brain into perceptible sounds.
Medical staff such as the nurse or medical interns and non-EEG (electroencephalogram) specialists can use the brain stethoscope to listen to and detect ongoing seizures in comatose patients.
The study was recently published in the journal Epilepsia.
A silent seizure or nonconvulsive status epilepticus (NCSE) is a neurological condition with no visible convulsions. This is a common problem in patients who are comatose or critically ill. Seizures which are undiagnosed can lead to more serious, life-threatening condition.
In addition, International League Against Epilepsy defines NCSE as a condition resulting either from the failure of the mechanisms responsible for seizure termination or from the initiation of mechanisms that lead to abnormally prolonged seizures. The NCSE patients with baseline coma or encephalopathy have more than 30 minutes of ictal EEG activity in any given hour.
According to Josef Parvizi, professor of Neurology and Neurological Sciences at Stanford University Medical Center, critical patients’ situation will require critical detection tool.
“Majority of seizures in critically ill patients are non-convulsive and many comatose patients do not recover because their brains keep seizing. Kids with these silent seizures, if they survive, will leave the hospitals with major cognitive impairment," said Parvizi.
|Source: Stanford University|
The Critical Scenario
A comatose patient enters into a state of unconsciousness or comatose wherein he cannot be awakened, he cannot respond to sounds, light or even normally painful stimuli. He cannot consciously speak, hear, feel or move. For a patient to be conscious, it will require functions of neurological components. The cerebral cortex, the gray matter responsible for the formation of the outer layer of the brain. And the reticular activating system located in the brainstem.
The old-fashioned way of seizure diagnosis of comatose patients involved a three-pronged process. A trained EEG technician will set up the sensors on a patient’s skull. These sensors will record the brain’s electrical activity. The technician will then record and send the result to a neurologist. Hours may have passed before the neurologist could see and make an analysis. The critical time is sacrificed before the patient can be actually and definitively diagnosed and treated for the seizure.
However, with brain stethoscope, the critical situation is handled real time. The device can assess the patient suspected of seizure or NCSE right away even by a non-EEG expert. Attending nurse or medical staff can promptly listen using the brain stethoscope and can readily point out seizure occurrence. This prompt response is critical to the patient’s treatment and recovery.
|Source: Stanford University|
Listening to the Brain
Parvizi explained that not all seizures may cause convulsions, where a patient goes through the fits, visibly shake and fall on the floor. This is not the case for comatose patients in the intensive care units(ICU)."Close to 90% of those patients will have silent seizures though not visible they can still damage the brain if they are prolonged” he said.
The idea of listening to the brain came from a concert Parvizi attended to one night. He was actually intrigued by a performance using data recorded by an instrument aboard the Voyager space probe. This gave him an idea what to do with the brain waves.
In collaboration with Chris Chafe, a music professor and a member of Bio-X and the Neurosciences Institute and under Bio-X seed grant, they were able to attach music synthesis to a person’s brain. Parvazi recalled, "Once he sent me the files and I listened to them, I was literally in shock because it was so intuitive." He was able to hear the transition from non-seizure to seizure so easily.
Parvazi worked with Babak Razavi, a clinical assistant professor of neurology and Kapil Gururangan, a medical student and looked into 84 brain waves samples of EEGs. About 32 of the samples were either the actual seizure or seizure-like brain waves.
About 34 medical students and 30 nurses at Stanford listened to the samples converted to music using Chafe's algorithm. Results showed that even without training in EEG diagnosis of epilepsy, the participants were able to discern seizures and seizure-like activity from normal brain waves. They were also correct in identifying the seizure-like samples, the normal activity sample three-quarters of the time.