Dataset Information

Complementary structural and functional abnormalities to localise epileptogenic tissue.

ABSTRACT:

Background

When investigating suitability for epilepsy surgery, people with drug-refractory focal epilepsy may have intracranial EEG (iEEG) electrodes implanted to localise seizure onset. Diffusion-weighted magnetic resonance imaging (dMRI) may be acquired to identify key white matter tracts for surgical avoidance. Here, we investigate whether structural connectivity abnormalities, inferred from dMRI, may be used in conjunction with functional iEEG abnormalities to aid localisation of the epileptogenic zone (EZ), improving surgical outcomes in epilepsy.

Methods

We retrospectively investigated data from 43 patients (42% female) with epilepsy who had surgery following iEEG. Twenty-five patients (58%) were free from disabling seizures (ILAE 1 or 2) at one year. Interictal iEEG functional, and dMRI structural connectivity abnormalities were quantified by comparison to a normative map and healthy controls. We explored whether the resection of maximal abnormalities related to improved surgical outcomes, in both modalities individually and concurrently. Additionally, we suggest how connectivity abnormalities may inform the placement of iEEG electrodes pre-surgically using a patient case study.

Findings

Seizure freedom was 15 times more likely in patients with resection of maximal connectivity and iEEG abnormalities (p = 0.008). Both modalities separately distinguished patient surgical outcome groups and when used simultaneously, a decision tree correctly separated 36 of 43 (84%) patients.

Interpretation

Our results suggest that both connectivity and iEEG abnormalities may localise epileptogenic tissue, and that these two modalities may provide complementary information in pre-surgical evaluations.

Funding

This research was funded by UKRI, CDT in Cloud Computing for Big Data, NIH, MRC, Wellcome Trust and Epilepsy Research UK.

SUBMITTER: Horsley JJ

PROVIDER: S-EPMC10630610 | biostudies-literature | 2023 Nov

REPOSITORIES: biostudies-literature

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Publications

Complementary structural and functional abnormalities to localise epileptogenic tissue.

Horsley Jonathan J JJ Thomas Rhys H RH Chowdhury Fahmida A FA Diehl Beate B McEvoy Andrew W AW Miserocchi Anna A de Tisi Jane J Vos Sjoerd B SB Walker Matthew C MC Winston Gavin P GP Duncan John S JS Wang Yujiang Y Taylor Peter N PN

EBioMedicine 20231027

<h4>Background</h4>When investigating suitability for epilepsy surgery, people with drug-refractory focal epilepsy may have intracranial EEG (iEEG) electrodes implanted to localise seizure onset. Diffusion-weighted magnetic resonance imaging (dMRI) may be acquired to identify key white matter tracts for surgical avoidance. Here, we investigate whether structural connectivity abnormalities, inferred from dMRI, may be used in conjunction with functional iEEG abnormalities to aid localisation of th ...[more]

PMID: 37898096

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Dataset Information

Complementary structural and functional abnormalities to localise epileptogenic tissue.

Background

Methods

Findings

Interpretation

Funding

Publications

Complementary structural and functional abnormalities to localise epileptogenic tissue.

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