RT Journal Article
SR Electronic
T1 Lesion-Specific Language Network Alterations in Temporal Lobe Epilepsy
JF American Journal of Neuroradiology
JO Am. J. Neuroradiol.
FD American Society of Neuroradiology
DO 10.3174/ajnr.A6350
A1 O. Foesleitner
A1 K.-H. Nenning
A1 L. Bartha-Doering
A1 C. Baumgartner
A1 E. Pataraia
A1 D. Moser
A1 M. Schwarz
A1 V. Schmidbauer
A1 J.A. Hainfellner
A1 T. Czech
A1 C. Dorfer
A1 G. Langs
A1 D. Prayer
A1 S. Bonelli
A1 G. Kasprian
YR 2020
UL http://www.ajnr.org/content/early/2020/01/02/ajnr.A6350.abstract
AB BACKGROUND AND PURPOSE: Temporal lobe epilepsy, structural or nonlesional, may negatively affect language function. However, little is known about the lesion-specific influence on language networks. We hypothesized that different epileptogenic lesions are related to distinct alterations in the functional language connectome detected by fMRI.MATERIALS AND METHODS: One hundred one patients with epilepsy due to mesiotemporal sclerosis (21 left, 22 right), low-grade mesiotemporal tumors (12 left), or nonlesional temporal lobe epilepsy (22 left, 24 right) and 22 healthy subjects performed 3T task-based language fMRI. Task-based activation maps (laterality indices) and functional connectivity analysis (global and connectivity strengths between language areas) were correlated with language scores.RESULTS: Laterality indices based on fMRI activation maps failed to discriminate among patient groups. Functional connectivity analysis revealed the most extended language network alterations in left mesiotemporal sclerosis (involving the left temporal pole, left inferior frontal gyrus, and bilateral premotor areas). The other patient groups showed less extended but also predominantly ipsilesional network changes compared with healthy controls. Left-to-right hippocampal connectivity strength correlated positively with naming function (P = .01), and connectivity strength between the left Wernicke area and the left hippocampus was linked to verbal fluency scores (P = .01) across all groups.CONCLUSIONS: Different pathologies underlying temporal lobe epilepsy are related to distinct alterations of the functional language connectome visualized by fMRI functional connectivity analysis. Network analysis allows new insights into language organization and provides possible imaging biomarkers for language function. These imaging findings emphasize the importance of a personalized treatment strategy in patients with epilepsy.FCfunctional connectivityHChippocampusLIlaterality indexMTSmesiotemporal sclerosisnl-TLEnonlesional TLETLEtemporal lobe epilepsy