KANSAS CITY, Kan. -- Through the application of mathematics, digital signal processing and computer technology, researchers at the University of Kansas Medical Center believe they have unlocked the complicated secret of predicting when a patient with epilepsy is about to have a seizure.
In recent studies of 125 seizures monitored and recorded at KU Medical Center, the technique has predicted seizures by up to three minutes in advance, according to Ivan Osorio, MD, director of the Comprehensive Epilepsy Center and associate professor of neurology. "This is the first time anyone has been able to predict when a seizure is about to happen. Prior to this, seizures were considered unpredictable," Osorio said.
The research is sponsored by funding from the KU Research Development Fund; College of Arts and Sciences; the surgery and neurology foundations at KU Medical Center; the National Institutes of Health; and the National Science Foundation's Research Experience for Undergraduate fund. Osorio and Mark Frei, PhD, from the Medical Center campus, along with John Ralston, professor of physics and astronomy; Josef Dorfmeister, professor of mathematics; and David Lerner, associate professor of mathematics, all of the KU-Lawrence campus, are co-developers of the technique to predict seizures. The project has been in development at KU Medical Center over the past three and a half years. Standard electroencephalograms (EEGs) can record when a seizure occurs. EEGs are tools used to measure electrical activity within the brain. By using the algorithm, researchers can now predict when a seizure is imminent.
"The algorithm measures brain activity and separates the signals into seizure and non-seizure components. This creates a ratio of seizure to non-seizure elements," Osorio said. While seizure and non-seizure components are present in the brain of a patient with epilepsy at all times, the moment the seizure components reach a certain critical level signals that a seizure is about to occur.
Epilepsy is caused by factors such as head trauma, brain tumors, strokes, infection, poisoning, oxygen deprivation or other events that cause scarring in the brain. This scarring acts as an irritant to the nerve cells which can trigger an abnormal electrical discharge, causing a seizure.
For patients with epilepsy, the implications of being able to reliably predict the onset of a seizure holds the promise for new, effective ways of combating epilepsy. "This may revolutionize the way we treat seizures," Osorio predicted.
Currently, seizures are controlled by a number of anti-convulsant drugs. Approximately 60 percent to 80 percent of persons with epilepsy achieve satisfactory control by taking these medications. For the majority of patients, the anti-convulsant medications are the most expensive part of treatment. For those who receive no benefits from anti-convulsants, surgical treatment may be an option.
Having a way to predict seizures can mean a seizure would be sensed before it occurs and could be prevented. Although the technology for preventing seizures may still be several years away, it may eventually be possible to implant a device in a patient's brain to sense and prevent an oncoming seizure. One possibility would be a device that would create a tiny voltage surge to "short-circuit" the electrical discharge that causes a seizures. Another possibility is an implanted drug pump that would send anti-convulsant medication into the brain when seizure component levels begin to rise.
"This is very exciting because it opens up new avenues for treatment," said Steven Wilkinson, MD, neurosurgeon. "It's theoretically possible that we might some day be able to implant a 'smart device' that could actually prevent seizures from occurring."
Osorio said the algorithm used in the epilepsy center has successfully predicted all types of seizures tested.
"This is a giant first step for improved treatment for epilepsy," said Susan Arthurs, a patient of Osorio's and founder and president of the Epilepsy Alliance, a new, grass-roots organization to give people with epilepsy a voice.
"It's very exciting to me, as someone with epilepsy, to see a whole different direction in the type of treatment for epilepsy," she said.