UW-Madison scientists to use high-density EEGs to benefit epilepsy patients

Jan. 21, 2014

University of Wisconsin researchers pioneered the use of high-density electro-encephalograph (HD-EEG) technology to study sleep patterns and the effects of meditation.

With support from a local grassroots organization, Lily's Fund for Epilepsy Research, UW-Madison researchers will now evaluate how this advanced technology might benefit people with epilepsy.

Giulio Tononi

Giulio Tononi

Typical EEG devices used in hospitals and clinics gather information about brain activity and seizures using 19 electrodes placed on the scalp. By comparison, HD-EEG devices use up to 256 electrodes.

More electrodes mean more data, usually a good thing. But so much data can lead to information overload. Physicians can analyze traditional EEG readouts with the naked eye, looking for telltale spikes that signal an epileptic seizure, but HD-EEGs produce incredibly dense readouts in which the hundreds of lines run together and become impossible to decipher.

During the last 10 years, Dr. Giulio Tononi, UW neuroscientist and psychiatrist, has led efforts to develop proprietary software that can help interpret the massive amounts of data generated by HD-EEG sleep studies. He believes the techniques might yield important breakthroughs for epilepsy patients.

Tononi's lab will receive $100,000 from Lily's Fund for Epilepsy Research during the next two years to see if HD-EEGs can help pinpoint the focal point of seizures in the brain, and map the pathways those seizures take through the brain.

Locating that point of origin is critical for epilepsy patients who require brain surgery. One in 26 people will develop epilepsy in their lifetime, and one-third of those patients cannot gain control of their seizures with medication alone. Doctors and patients may opt for surgery, but only if the origin of seizures in the brain can be pinpointed accurately.

Because a traditional EEG does not provide enough detail, neurosurgeons rely on intracranial EEG studies, in which electrodes are placed directly on the brain itself. This invasive approach increases the risk of infection and other complications. HD-EEG technology may offer an accurate way to find the source of those seizures, potentially reducing the need to resort to the invasive intracranial approach.

“This is a very novel approach — one that might yield insights on the pathophysiology of seizures.”

Giulio Tononi

Scientists believe the method might also predict the pathways of the seizures and how they move across the brain, which would represent a major breakthrough in epilepsy research.

"If high-density EEGs can be used to accurately locate through which pathways seizures spread from their focal point to invade the rest of the brain, physicians may be able to develop new ways to stop them from propagating when brain surgery is performed. For epilepsy patients, this could minimize the number of tests and avoid invasive monitoring that requires multiple surgeries," said Tononi.

"Over the next two years, we hope to study at least 20 patients, examining how seizures spread through the brain's cortex. This is a very novel approach — one that might yield insights on the pathophysiology of seizures," said Tononi.

Lily's Fund announced the creation of new competitive "Grace Grants" at their annual luau fundraiser in January 2013. While continuing to underwrite post-doctoral and graduate research fellowships at UW-Madison's School of Medicine and Public Health, Lily's Fund volunteers designed the new grant program to spark innovative early-stage epilepsy research. The new grant is named in honor of a Verona teen, Grace Penwell, who lives with Dravet's Syndrome, a severe form of epilepsy and inspires others with her courage and spark.

Lily's Fund, established in 2006, is an all-volunteer organization that celebrates and supports epilepsy-related research at UW-Madison. The sixth annual Lily's Luau will be held Saturday, Jan. 25 at UW-Madison's Union South.