Widespread grey matter changes and hemodynamic correlates to interictal epileptiform discharges in pharmacoresistant mesial temporal epilepsy.

Abstract

Focal onset epilepsies most often occur in the temporal lobes. To improve diagnosis and therapy of patients suffering from pharmacoresistant temporal lobe epilepsy it is highly important to better understand the underlying functional and structural networks. In mesial temporal lobe epilepsy (MTLE) widespread functional networks are involved in seizure generation and propagation. In this study we have analyzed the spatial distribution of hemodynamic correlates (HC) to interictal epileptiform discharges on simultaneous EEG/fMRI recordings and relative grey matter volume (rGMV) reductions in 10 patients with MTLE. HC occurred beyond the seizure onset zone in the hippocampus, in the ipsilateral insular/operculum, temporo-polar and lateral neocortex, cerebellum, along the central sulcus and bilaterally in the cingulate gyrus. rGMV reductions were detected in the middle temporal gyrus, inferior temporal gyrus and uncus to the hippocampus, the insula, the posterior cingulate and the anterior lobe of the cerebellum. Overlaps between HC and decreased rGMV were detected along the mesolimbic network ipsilateral to the seizure onset zone. We conclude that interictal epileptic activity in MTLE induces widespread metabolic changes in functional networks involved in MTLE seizure activity. These functional networks are spatially overlapping with areas that show a reduction in relative grey matter volumes.

• Authors: Roland Wiest, Lea Estermann, Olivier Scheidegger, Christian Rummel, Kay Jann, Margitta Seeck, Kaspar Schindler, Martinus Hauf
• Journal: Journal of neurology (J Neurol) Vol. 260 Issue 6 Pg. 1601-10 (Jun 2013) ISSN: 1432-1459 [Electronic] Germany
• PMID: 23355177 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)

Topics

• Adult
• Aged
• Brain (physiopathology)
• Electroencephalography
• Epilepsy, Temporal Lobe (physiopathology)
• Female
• Hemodynamics (physiology)
• Humans
• Image Interpretation, Computer-Assisted
• Magnetic Resonance Imaging
• Male
• Middle Aged
• Nerve Net (physiopathology)
• Seizures (physiopathology)
• Signal Processing, Computer-Assisted
• Young Adult