Purpose: Electroencephalography/functional magnetic resonance imaging (EEG/fMRI) has been proposed recently as a tool to study electrophysiological activity and, consequently, detect brain regions activated during epileptiform EEG abnormalities. The purpose of the study was to review our two-year experience with studying ictal and interictal activities in patients with epilepsy.
Methods: Using EEG/fMRI, we studied hemodynamic changes associated with ictal and interictal EEG abnormalities in 43 patients with partial (31 cases) or generalized (12 cases) epilepsy. Using two different paradigms (block design and event-related design), we studied several forms of EEG activity consisting of (i) interictal abnormalities constantly elicitable by specific stimulation (8 cases); (ii) focal and generalized interictal activity, such as focal spikes or typical and atypical generalized spike-and-wave discharges (18 cases); and (iii) focal and generalized ictal electro-clinical activity, such as tonic seizures or pseudo-absences in frontal lobe epilepsy, typical absences in idiopathic generalized epilepsy, complex partial seizures in temporal lobe epilepsy, and perisylvian seizures in special syndromes (17 patients).
Results: EEG/fMRI revealed clear hemodynamic changes related to EEG abnormalities in 21 patients. In 18 of these patients, the changes were highly concordant with electro-clinical findings. In the remaining 22 patients, fMRI analysis data failed to show activation or deactivation clusters, probably owing either to lack or inadequate amount of temporal distribution of abnormal EEG activity, or to intrinsic methodological problems.
Conclusions: By defining the electro-clinical and hemodynamic correlates of EEG activity, fMRI may shed light on the neurophysiological mechanisms underlying epileptic phenomena. However, as several methodological issues have yet to be addressed, further studies are warranted to assess the reliability and usefulness of EEG/fMRI in clinical practice.
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http://dx.doi.org/10.1111/j.1528-1167.2006.00878.x | DOI Listing |
BMC Med Inform Decis Mak
January 2025
The First Affiliated Hospital, and College of Clinical Medicine of Henan University of Science and Technology, Luoyang, China.
Background: The diagnosis and treatment of epilepsy continue to face numerous challenges, highlighting the urgent need for the development of rapid, accurate, and non-invasive methods for seizure detection. In recent years, advancements in the analysis of electroencephalogram (EEG) signals have garnered widespread attention, particularly in the area of seizure recognition.
Methods: A novel hybrid deep learning approach that combines feature fusion for efficient seizure detection is proposed in this study.
Front Neurol
December 2024
Division of Neurology, Department of Pediatrics, McMaster Children's Hospital, Hamilton, ON, Canada.
Introduction: This study investigated low-density scalp electrical source imaging of the ictal onset zone and interictal spike ripple high-frequency oscillation networks using source coherence maps in the pediatric epilepsy surgical workup. Intracranial monitoring, the gold standard for determining epileptogenic zones, has limited spatial sampling. Source coherence analysis presents a promising new non-invasive technique.
View Article and Find Full Text PDFNeurobiol Dis
December 2024
Institute of Physiology I, Münster University, Münster, Germany. Electronic address:
Spike-wave-discharges (SWD) are the electrophysiological hallmark of absence epilepsy. SWD are generated in the thalamo-cortical network and a seizure onset zone was identified in the somatosensory cortex (S1). We have shown before that inhibition of the centromedian thalamic nucleus (CM) in GAERS rats resulted in a selective suppression of the spike component while rhythmic cortical 5-9 Hz oscillations remained present.
View Article and Find Full Text PDFJ Headache Pain
December 2024
Department of Neurology, Headache Medical Center, Linz, Austria.
The association between migraine and cognitive function has been studied during the last decade, however, this relationship is not well established. As migraine prevalence is highest between the ages of 30-40, aligning with some of our most productive years, we must understand cognitive changes within this disorder. Cognitive impairment potentially limits social and professional interactions, thus negatively impacting quality of life.
View Article and Find Full Text PDFEpileptic Disord
December 2024
IRCCS Ospedale Policlinico San Martino, Division of Clinical Neurophysiology and Epilepsy Center, Genoa, Italy.
Objective: The aim of this study was to describe the clinical features of contactin-associated protein-like 2 (CASPR2)-IgG-associated seizures.
Methods: Nine patients were retrospectively collected from two epilepsy centers. For each patient we obtained a full clinical, neurophysiological, and MRI study along with detection of antineuronal autoantibodies from serum and CSF.
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