Language Dominance in Patients With Malformations of Cortical Development and Epilepsy

Giorgi Kuchukhidze; Christian Siedentopf; Iris Unterberger; Florian Koppelstaetter; Martin Kronbichler; Laura Zamarian; Edda Haberlandt; Anja Ischebeck; Margarete Delazer; Stephan Felber; Eugen Trinka

doi:10.3389/fneur.2019.01209

Language Dominance in Patients With Malformations of Cortical Development and Epilepsy

Front Neurol. 2019 Nov 21:10:1209. doi: 10.3389/fneur.2019.01209. eCollection 2019.

Authors

Giorgi Kuchukhidze^{1

2}, Christian Siedentopf³, Iris Unterberger¹, Florian Koppelstaetter^{3

4}, Martin Kronbichler^{5

6

7}, Laura Zamarian¹, Edda Haberlandt^{8

9}, Anja Ischebeck¹⁰, Margarete Delazer¹, Stephan Felber¹¹, Eugen Trinka^{1

2

7}

Affiliations

¹ Department of Neurology, Medical University of Innsbruck, Innsbruck, Austria.
² Department of Neurology, Christian Doppler Klinik, Paracelsus Medical University of Salzburg, Salzburg, Austria.
³ Department of Neuroradiology, Medical University of Innsbruck, Innsbruck, Austria.
⁴ Department of Radiology, Sanatorium Kettenbrücke, Innsbruck, Austria.
⁵ Neuroscience Institute, Christian Doppler Klinik, Paracelsus Medical University of Salzburg, Salzburg, Austria.
⁶ Department of Psychology, University of Salzburg, Salzburg, Austria.
⁷ Centre for Cognitive Neuroscience, University of Salzburg, Salzburg, Austria.
⁸ Department of Pediatrics I, Medical University of Innsbruck, Innsbruck, Austria.
⁹ Department of Pediatrics, City Hospital, Dornbirn, Austria.
¹⁰ Institute of Psychology, University of Graz, Graz, Austria.
¹¹ Department of Diagnostic and Interventional Radiology and Neuroradiology, Gemeinschaftsklinikum Mittelrhein, Koblenz, Germany.

Abstract

Background: Language function may be reorganized in patients with malformations of cortical development (MCD). This prospective cohort study aimed in assessing language dominance in a large group of patients with MCD and epilepsy using functional MRI (fMRI). Methods: Sixty-eight patients (40 women) aged 10-73 years (median, 28.0; interquartile range, 19) with MCD and epilepsy underwent 1.5 T MRI and fMRI (word generation task). Single-subject image analysis was performed with statistical parametric mapping (SPM12). Language lateralization indices (LIs) were defined for statistically significantly activated voxels in Broca's and Wernicke's areas using the formula: LI = (V _L - V _R)/(V _L + V _R) × 100, where V _L and V _R were sets of activated voxels on the left and on the right, respectively. Language laterality was considered typical if LI was between +20 and +100 or atypical if LI was between +19 and -100. Results: fMRI signal was elicited in 55 of 68 (81%) patients. In 18 of 55 (33%) patients, language dominance was typical, and in 37 of 55 (67%) patients, atypical (in 68%, right hemispheric; in 32%, bilateral). Language dominance was not influenced by handedness, electroclinical, and imaging features. Conclusions: In this prospective study on a large group of patients with MCD and epilepsy, about two-thirds had atypical language dominance. These results may contribute to assessing risks of postsurgical language deficits and could assist in planning of "cortical mapping" with intracranial electrodes in patients who undergo presurgical assessment.

Keywords: epilepsy; epilepsy surgery; functional MRI; language; malformations of cortical development.