Lydia Wachsmuth1, Florian Schmid1, Franziska Albers1, Annika Lüttjohann2, Thomas Budde2, and Cornelius Faber1
1Department of Clinical Radiology, University of Münster, Münster, Germany, 2Institute of Physiology I, University of Münster, Münster, Germany
Simultaneous
BOLD fMRI and optical Ca2+ recordings using the genetically encoded
calcium indicator GCaMP were performed in a rat model of absence epilepsy
(GAERS) for seizure mapping. Spike-and-wave
discharge onset times and durations were derived from Ca2+
recordings and used for an event-related analysis with different hemodynamic
response functions. BOLD maps showed large scale activations in cortical and
subcortical areas, with delayed responses in subcortical areas. In contrast to
electrophysiological recordings, Ca2+ recordings are not disturbed
by MRI. They allow for cell-specific correlation with the hemodynamic response
and provide a tool to obtain epileptic seizure maps with higher specificity.