Arcuate fasciculus cortico-cortical and axono-cortical evoked potentials with post-resection excitability changes in perisylvian glioma

07/08/2026

AI Summary

AF-CCEP and AF-ACEP are feasible intraoperative adjuncts for monitoring arcuate fasciculus during perisylvian supratentorial tumour surgery across multiple tertiary centres.
Post-resection N1 peak amplitude increased cohort wide while onset latency remained stable, suggesting intact AF conduction with increased cortical excitability after tumour removal.
Signal degradation correlated with postoperative language deficits; AF-CCEP and AF-ACEP may provide monitoring when awake craniotomy is contraindicated.

Clin Neurophysiol Pract. 2026 Jul 21;11:629-641. doi: 10.1016/j.cnp.2026.07.013. eCollection 2026.

ABSTRACT

OBJECTIVE: To evaluate the feasibility and clinical utility of arcuate fasciculus cortico-cortical evoked potentials (AF-CCEP) and axono-cortical evoked potentials (AF-ACEP) during perisylvian supratentorial tumor surgery, and examine whether morphology changes serve as electrophysiological biomarkers of postoperative language function.

METHODS: We analysed 19 patients with tumors involving or adjacent to the arcuate fasciculus across multiple tertiary centers. AF-CCEPs were elicited by monophasic stimulation toward the inferior frontal gyrus and recorded over the middle or posterior superior temporal gyrus; AF-ACEPs were obtained via subcortical bipolar stimulation. Primary outcomes explored N1 morphology pre- and post-resection, with subgroup analyses by tumor grade, location, montage, and anesthesia.

RESULTS: 822 AF-CCEPs and 134 AF-ACEPs were acquired intraoperatively; 133 and 37 matched recordings were included for analysis, respectively. Post-resection N1 peak amplitude increased cohort-wide, while onset latency remained stable. One patient demonstrated signal loss associated with postoperative aphasia. AF-ACEP amplitudes were higher under general anesthesia, in higher-grade tumors, and with proximity to the AF on tractography.

CONCLUSIONS: AF-CCEP and AF-ACEP are feasible intraoperative adjuncts, with signal degradation associated with language morbidity. Post-resection amplitude increases may reflect intact AF conduction with increased cortical excitability following tumor removal.

SIGNIFICANCE: When awake craniotomy is contraindicated, AF-CCEP and AF-ACEP may represent a viable alternative for monitoring AF integrity and reducing postoperative language morbidity.

PMID:42564666 | PMC:PMC13445182 | DOI:10.1016/j.cnp.2026.07.013

Document this CPD