Magnetoencephalography in Absence Seizures
SeizuresBackground: An absence seizure is a type of seizure that usually begins in childhood and goes away by early adulthood. Scientists do not yet know where absence seizures begin in the brain. Some evidence suggests that these seizures begin in the thalamus, a structure deep in the brain, but other studies suggest that they begin in the frontal cortex, at the front part of the brain. Magnetoencephalography is a type of brain scanning procedure that is useful in determining information about what happens to the brain during epileptic seizures. Understanding where absence seizures come from may help doctors find new treatments for them. Objectives: To gain a better understanding of which parts of the brain are affected in absence seizures. Eligibility: Patients 7 to 35 years of age who have been diagnosed with absence seizures. Design: Procedures are for research purposes only, not to diagnose or treat a particular medical condition. Two outpatient visits to the National Institutes of Health Clinical Center: evaluation and scanning. Researchers will evaluate potential participants with a medical history, physical examination, and electroencephalography (EEG). These tests will be performed under another protocol, 01-N-0139. Patients will undergo magnetoencephalography (MEG) and magnetic resonance imaging (MRI) of the brain. The study procedures will be performed one time; however, an MEG or MRI scan may need to be repeated for technical reasons. Researchers will not do more than two MEG or MRI scans. The MEG will record very small magnetic field changes produced by the activity of the brain. An EEG will be recorded at the same time as the MEG. The MRI will use a magnetic field to take pictures of the inside of the brain. The MEG will take 3 hours to complete (2 hours for preparation, 1 hour in the scanner). The MRI will take approximately 1 hour.
Functional Magnetic Resonance Imaging (fMRI) Study of Memory in Children
Childhood Absence Epilepsy [Pyknolepsy]Memory is a cognitive function whose development is still poorly documented in children, but which is often disturbed in temporal epilepsy. There are no studies about the disorders of episodic memory. The investigations using functional MRI (fMRI) are scarce, they do not involve this field and none are dedicated to children. The objectives of this project are to study the neuronal networks involved in episodic memory in normal children, as well as the disorders of episodic memory in children with epilepsy and the mechanisms of cognitive and cerebral reorganization in epilepsy.
Why Are Patients With Absence Seizures Absent? A Brain Imaging Study
Childhood Absence EpilepsyOur study examines which different brain regions are involved in child absence seizures and how they are related to attention and cognition.
Concomitant High-resolution Recording of Haemodynamic and Electrical Activities of Children With...
EpilepsyThis study, conducted in children with typical or atypical "absence" epilepsy, will consist of noninvasive recording of the metabolic activity of the brain concomitantly with electroencephalographic recording during seizures without the need for any additional examination. This examination will be performed by combining near-infrared spectroscopy (NIRS) optical imaging and Electroencephalography (EEG) in a simultaneous High-Resolution (HR) recording. Surface electroencephalography (EEG) is a valuable tool to assess neuronal dysfunction from a functional point of view and is used in the routine follow-up of epileptic children. Optical imaging is a recent and promising medical imaging technique, which uses near-infrared light. This rapid, noninvasive and harmless quantitative technique can be easily used at the child's bedside or in the ward and provides metabolic information on brain functioning.
Longitudinal Early Epilepsy Study
Absence EpilepsyEpilepsy1 moreThis longitudinal study will focus on the cognitive and brain development of children with absence epilepsy. In addition, the investigators aim to identify prognostic factors for cognitive deterioration and/or poor seizure control in these children.