Cerebral lesions can impair fMRI-based language lateralization.

Area of Science:

• Neuroimaging
• Neurology
• Epilepsy Research

Background:

• Concerns exist regarding functional magnetic resonance imaging (fMRI) reliability near cerebral lesions.
• This potential impairment may affect fMRI's clinical validity for presurgical language lateralization.

Purpose of the Study:

• To investigate if lesion type and localization systematically affect fMRI results.
• To determine the impact of cerebral lesions on fMRI-based language lateralization.

Main Methods:

• Classified epilepsy-related lesions based on BOLD-effect interference and proximity to volumes of interest (VOIs).
• Evaluated lesion effects in 238 epilepsy patients, including 37 with Wada test-confirmed left-language dominance.

Main Results:

• Patients with fMRI-critical lesions (e.g., cavernomas, gliomas, mass defects, atrophy) near VOIs showed lower lateralization indices (LIs).
• These patients more frequently exhibited discordant language lateralization compared to the Wada test.

Conclusions:

• Cerebral lesions significantly impact fMRI language lateralization reliability.
• Specific lesion types and locations pose greater risks to fMRI accuracy.
• Routine application of fMRI in patients with cerebral lesions requires careful consideration.