Faculty Collaboration Database

Localizing epileptogenic regions in partial epilepsy using three-dimensional statistical parametric maps of background EEG source spectra. Neuroimage 2008 Feb 01;39(3):1257-65

Date

11/21/2007

Pubmed ID

18024085

DOI

10.1016/j.neuroimage.2007.09.041

Scopus ID

2-s2.0-37849005346 (requires institutional sign-in at Scopus site)   13 Citations

Abstract

This preliminary study sought to localize epileptogenic regions in patients with partial epilepsy by analysis of interictal EEG activity utilizing variable resolution electromagnetic tomography (VARETA), a three-dimensional quantitative electroencephalographic (QEEG) frequency-domain distributed source modeling technique. The very narrow band (VNB) spectra spanned the frequency range 0.39 Hz to 19.1 Hz, in 0.39 Hz steps. These VNB spectra were compared to normative data and transformed to provide Z-scores for every scalp derivation, and the spatial distributions of the probable EEG generators of the most abnormal values were displayed on slices from a probabilistic MRI atlas. Each voxel was color-coded to represent the significance of the deviation relative to age appropriate normative values. We compared the resulting three-dimensional images to the localization of epileptogenic regions based on invasive intracranial EEG recordings of seizure onsets. The VARETA image indicated abnormal interictal spectral power values in regions of seizure onset identified by invasive monitoring, mainly in delta and theta range (1.5 to 8.0 Hz). The VARETA localization of the most abnormal voxel was congruent with the epileptogenic regions identified by intracranial recordings with regard to hemisphere in all 6 cases, and with regard to lobe in 5 cases. In contrast, abnormal findings with routine EEG agreed with invasive monitoring with regard to hemisphere in 3 cases and with regard to lobe in 2 cases. These results suggest that analysis of background interictal EEG utilizing distributed source models should be investigated further in clinical epilepsy.

Author List

Alper K, Raghavan M, Isenhart R, Howard B, Doyle W, John R, Prichep L

Author

Manoj Raghavan MD, PhD Professor in the Neurology department at Medical College of Wisconsin

MESH terms used to index this publication - Major topics in bold

Adult
Algorithms
Brain Mapping
Electroencephalography
Epilepsies, Partial
Female
Functional Laterality
Humans
Image Processing, Computer-Assisted
Magnetic Resonance Imaging
Male
Middle Aged
Neuropsychological Tests
Reproducibility of Results
Seizures