WINSTON-SALEM, N.C. – Monday, Feb. 7, 2011 – Have you evercompletely lost touch with your surroundings, just for a moment, and not realized it until your awareness returned?
Imagine this happening up to 200 times a day and you will understand the challenge facing children with severe childhood absence epilepsy.
Formerly known as petit mal epilepsy, the resulting seizures are usually brief, lasting less than 15 seconds, and patients are often described as staring into space. The seizure is caused by abnormal electrical activity – highly rhythmic waves – that eventually encompass the entire brain. The disorder occurs in patients under age 20 and most commonly in children ages 6 to 12. It affects eight out of every 100,000 people, but doctors believe that this number is likely an underestimate because it is sometimes mistaken for a learning disability.
Current treatment for the disorder involves the use of extremely powerful drugs in an attempt to control the seizures. Some of these drugs, however, have serious side effects including sleepiness, and some patients don't respond well to the medicine.
Scientists at Wake Forest Baptist Medical Center (WFBMC) are trying to determine whether these seizures can be “seen” prior to the involvement of the whole brain. If this is possible, then perhaps less harmful drugs could be used to interrupt the seizures before they start. The team recently shared the latest findings from their research into childhood absence seizures in a presentation at the annual meeting of the American Epilepsy Society.
To see into the brain, the scientists use an imaging technology called magnetoencephalography (MEG). This window into the brain allows researchers to observe what happens prior to, during, and after these seizures as they occur. The hope is that if seizures can be imaged prior to being triggered, perhaps they can be predicted.
“We have found a way to map abnormal activity arising in specific regions of the brain using MEG,” said neuroscientist Dwayne W. Godwin, Ph.D., who co-authored the study with Jennifer Stapleton-Kotloski, Ph.D. “The mathematical principle is similar to locating the position of a specific cell phone by calculating the proximity to cell phone towers,” Godwin said. “We are using this high resolution method to determine whether tiny signals in small brain regions may lead to big waves, like a pebble dropping into a pool. If we can catch the pebble, we hope we can stop the waves.”
The researchers are finding that the ripples of these smaller spikes occur in the small regions of the frontal lobes of the brain that are responsible for consciousness. The discovery helps explain why children who have these seizures often lose awareness.
The researchers are also developing the technology to study other brain disorders, such as seizures arising after traumatic brain injury or after withdrawal from drugs and alcohol. Wake Forest Baptist is home to one of only a handful of these high-resolution MEG scanners in the country.
Other Wake Forest Baptist researchers involved in the study include Cormac O’Donovan, M.D., Robert Kotloski, M.D., Bill Boles, M.D., and Tiffany Huitt, Ph.D.