Novel fMRI applications in childhood epilepsy increase understanding of seizure impacts

December 13, 2017

WASHINGTON - (December 11, 2017) - Functional magnetic resonance imaging (fMRI) has allowed researchers to map the memory functions that are often impaired within the brains of children with epilepsy. Additionally, a separate study of a novel application of resting-state fMRI, where the patient does not have to complete tasks, demonstrated the potential for clinicians to use non-invasive fMRI for language assessment for children who are too young or impaired to follow task directions in traditional fMRI studies. Both studies were presented at the American Epilepsy Society Annual Meeting in Washington, D.C., last week.

fMRI tool tracks verbal and visual memory in children with epilepsy

The first study, which developed a new fMRI task/activity designed to track verbal and visual memory, is one of only a few pediatric memory studies using fMRI in children with epilepsy.

"Non-invasive fMRI is a powerful tool and an excellent alternative to more invasive testing to measure language and memory," says William D. Gaillard, M.D., a senior author of the study and chief of Child Neurology, Epilepsy and Neurophysiology who also directs the Comprehensive Pediatric Epilepsy Program at Children's National Health System. "This study allowed us to elicit hippocampal and parahippocampal activation in children with epilepsy and compare the findings with controls to demonstrate that fMRI may be used effectively to track memory and recall ability in children with epilepsy."

The study included twenty-one children with focal epilepsy and 17 controls to assess how well a new paired association learning fMRI task captured the verbal and visual memory activities of the hippocampus and the parahippocampal regions of the brain--which are known to play significant roles in verbal and visual memory.

Though a small sample, the results suggest that fMRI memory tasks such as the one tested can be used to produce findings that are sensitive to the hippocampal activity differences in children, which may lead to an important clinical tool for presurgical planning.

Mapping language skills using resting state fMRI before epilepsy surgery

A second study demonstrated the ability of functional connectivity analysis within a resting-state fMRI to assess language laterality, meaning to help determine the dominant side of the brain controlling language, when compared with the current standard of a language-task fMRI measure.

"Mapping language prior to epilepsy surgery is vital to evaluating the risks of postoperative deficits in children," says Dr. Gaillard. "But asking a very young or intellectually impaired child to complete the tasks necessary for reliable mapping using standard fMRI practices is limited by the child's ability to comply with the demands of a task."

Unlike traditional fMRI where a subject performs a series of validated tasks to "light up" or activate the target regions of the brain, resting-state fMRI captures regional brain activity without the additional stimulus of a task to complete. The data-driven method of identifying language laterality through functional connectivity analysis was developed previously at Children's National and applied in this setting to test its ability to map the dominant regions of the brain controlling language.

The study found that when compared with typical language assessment tasks, resting state fMRI functional connectivity analysis matched the results of the task activity findings slightly more than two thirds of the time. While more research is needed, the study succeeded in demonstrating the potential of data-driven methods to establish reliable language laterality even without a task-based fMRI.

"Our hope is that one day we may be able to expand the use of clinical fMRI as an effective, noninvasive tool for language mapping prior to epilepsy surgery by eliminating task completion as a requirement for success," says Madison Berl, PhD, a study author, director of research in the Division of Pediatric Neuropsychology, and a pediatric neuropsychologist in the Comprehensive Pediatric Epilepsy Program at Children's National.

The American Epilepsy Society Annual Meeting is the largest professional gathering on epilepsy in the world.
-end-
About Children's National Health System

Children's National Health System, based in Washington, D.C., has been serving the nation's children since 1870. Children's National is #1 for babies and ranked in every specialty evaluated by U.S. News & World Report including placement in the top 10 for: Cancer (#7), Neurology and Neurosurgery (#9), Orthopedics (#9) and Nephrology (#10). Children's National has been designated two times as a Magnet® hospital, a designation given to hospitals that demonstrate the highest standards of nursing and patient care delivery. This pediatric academic health system offers expert care through a convenient, community-based primary care network and specialty outpatient centers. Home to the Children's Research Institute and the Sheikh Zayed Institute for Pediatric Surgical Innovation, Children's National is one of the nation's top NIH-funded pediatric institutions. Children's National is recognized for its expertise and innovation in pediatric care and as a strong voice for children through advocacy at the local, regional and national levels. For more information, visit ChildrensNational.org, or follow us on Facebook and Twitter.

Children's National Health System

Related Epilepsy Articles from Brightsurf:

Focal epilepsy often overlooked
Having subtler symptoms, a form of epilepsy that affects only one part of the brain often goes undiagnosed long enough to cause unexpected seizures that contribute to car crashes, a new study finds.

Antibodies in the brain trigger epilepsy
Certain forms of epilepsy are accompanied by inflammation of important brain regions.

Breaching the brain's defense causes epilepsy
Epileptic seizures can happen to anyone. But how do they occur and what initiates such a rapid response?

Using connectomics to understand epilepsy
Abnormalities in structural brain networks and how brain regions communicate may underlie a variety of disorders, including epilepsy, which is one focus of a two-part Special Issue on the Brain Connectome in Brain Connectivity, a peer-reviewed journal from Mary Ann Liebert, Inc., publishers.

Epilepsy: Triangular relationship in the brain
When an epileptic seizure occurs in the brain, the nerve cells lose their usual pattern and fire in a very fast rhythm.

How concussions may lead to epilepsy
Researchers have identified a cellular response to repeated concussions that may contribute to seizures in mice like those observed following traumatic brain injury in humans.

Understanding epilepsy in pediatric tumors
A KAIST research team led by Professor Jeong Ho Lee of the Graduate School of Medical Science and Engineering has recently identified a neuronal BRAF somatic mutation that causes intrinsic epileptogenicity in pediatric brain tumors.

Can medical marijuana help treat intractable epilepsy?
A new British Journal of Clinical Pharmacology review examines the potential of medicinal cannabis -- or medical marijuana -- for helping patients with intractable epilepsy, in which seizures fail to come under control with standard anticonvulsant treatment.

Fertility rates no different for women with epilepsy
'Myth-busting' study among women with no history of infertility finds that those with epilepsy are just as likely to become pregnant as those without.

Do women with epilepsy have similar likelihood of pregnancy?
Women with epilepsy without a history of infertility or related disorders who wanted to become pregnant were about as likely as their peers without epilepsy to become pregnant.

Read More: Epilepsy News and Epilepsy Current Events
Brightsurf.com is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to Amazon.com.