Dataset Information

Altered functional connectivity in seizure onset zones revealed by fMRI intrinsic connectivity.

ABSTRACT:

Objective

The purpose of this study was to investigate functional connectivity (FC) changes in epileptogenic networks in intractable partial epilepsy obtained from resting-state fMRI by using intrinsic connectivity contrast (ICC), a voxel-based network measure of degree that reflects the number of connections to each voxel.

Methods

We measured differences between intrahemispheric- and interhemispheric-ICC (ICCintra-inter) that could reveal localized connectivity abnormalities in epileptogenic zones while more global network changes would be eliminated when subtracting these values. The ICCintra-inter map was compared with the seizure onset zone (SOZ) based on intracranial EEG (icEEG) recordings in 29 patients with at least 1 year of postsurgical follow-up. Two independent reviewers blindly interpreted the icEEG and fMRI data, and the concordance rates were compared for various clinical factors.

Results

Concordance between the icEEG SOZ and ICCintra-inter map was observed in 72.4% (21/29) of the patients, which was higher in patients with good surgical outcome, especially in those patients with temporal lobe epilepsy (TLE) or lateral temporal seizure localization. Concordance was also better in the extratemporal lobe epilepsy than the TLE group. In 85.7% (18/21) of the cases, the ICCintra-inter values were negative in the SOZ, indicating decreased FC within the epileptic hemisphere relative to between hemispheres.

Conclusions

Assessing alterations in FC using fMRI-ICC map can help localize the SOZ, which has potential as a noninvasive presurgical diagnostic tool to improve surgical outcome. In addition, the method reveals that, in focal epilepsy, both intrahemispheric- and interhemispheric-FC may be altered, in the presence of both regional as well as global network abnormalities.

SUBMITTER: Lee HW

PROVIDER: S-EPMC4277677 | biostudies-literature | 2014 Dec

REPOSITORIES: biostudies-literature

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Publications

Altered functional connectivity in seizure onset zones revealed by fMRI intrinsic connectivity.

Lee Hyang Woon HW Arora Jagriti J Papademetris Xenophon X Tokoglu Fuyuze F Negishi Michiro M Scheinost Dustin D Farooque Pue P Blumenfeld Hal H Spencer Dennis D DD Constable R Todd RT

Neurology 20141112 24

<h4>Objective</h4>The purpose of this study was to investigate functional connectivity (FC) changes in epileptogenic networks in intractable partial epilepsy obtained from resting-state fMRI by using intrinsic connectivity contrast (ICC), a voxel-based network measure of degree that reflects the number of connections to each voxel.<h4>Methods</h4>We measured differences between intrahemispheric- and interhemispheric-ICC (ICCintra-inter) that could reveal localized connectivity abnormalities in e ...[more]

PMID: 25391304

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Dataset Information

Altered functional connectivity in seizure onset zones revealed by fMRI intrinsic connectivity.

Objective

Methods

Results

Conclusions

Publications

Altered functional connectivity in seizure onset zones revealed by fMRI intrinsic connectivity.

Similar Datasets

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