White matter alterations in focal to bilateral tonic-clonic seizures

Christina Maher; Arkiev D'Souza; Rui Zeng; Michael Barnett; Omid Kavehei; Armin Nikpour; Chenyu Wang

doi:10.3389/fneur.2022.972590

White matter alterations in focal to bilateral tonic-clonic seizures

Front Neurol. 2022 Sep 14:13:972590. doi: 10.3389/fneur.2022.972590. eCollection 2022.

Authors

Christina Maher^{1

2

3}, Arkiev D'Souza^{2

4}, Rui Zeng^{2

4}, Michael Barnett^{2

5

6}, Omid Kavehei^{1

3}, Armin Nikpour^{5

7}, Chenyu Wang^{2

4

6}

Affiliations

¹ School of Biomedical Engineering, Faculty of Engineering, The University of Sydney, Sydney, NSW, Australia.
² Brain and Mind Centre, The University of Sydney, Sydney, NSW, Australia.
³ Australian Research Council Training Centre for Innovative BioEngineering, The University of Sydney, Sydney, NSW, Australia.
⁴ Translational Research Collective, Faculty of Medicine and Health, The University of Sydney, Sydney, NSW, Australia.
⁵ Department of Neurology, Royal Prince Alfred Hospital, Camperdown, NSW, Australia.
⁶ Sydney Neuroimaging Analysis Centre, Camperdown, NSW, Australia.
⁷ Central Clinical School, Faculty of Medicine and Health, The University of Sydney, Sydney, NSW, Australia.

Abstract

We examined the white matter of patients with and without focal to bilateral tonic-clonic seizures (FBTCS), and control participants. A neural network based tract segmentation model (Tractseg) was used to isolate tract-specific, track-weighted tensor-based measurements from the tracts of interest. We compared the group differences in the track-weighted tensor-based measurements derived from whole and hemispheric tracts. We identified several regions that displayed significantly altered white matter in patients with focal epilepsy compared to controls. Furthermore, patients without FBTCS showed significantly increased white matter disruption in the inferior fronto-occipital fascicle and the striato-occipital tract. In contrast, the track-weighted tensor-based measurements from the FBTCS cohort exhibited a stronger resemblance to the healthy controls (compared to the non-FBTCS group). Our findings revealed marked alterations in a range of subcortical tracts considered critical in the genesis of seizures in focal epilepsy. Our novel application of tract-specific, track-weighted tensor-based measurements to a new clinical dataset aided the elucidation of specific tracts that may act as a predictive biomarker to distinguish patients likely to develop FBTCS.

Keywords: diffusion MRI; focal epilepsy; focal to bilateral tonic-clonic seizure; microstructural; tensor-based imaging; track-weighted imaging; white matter.