Functional MRI for bilingual epilepsy surgery patients: serving a diverse pediatric cohort

Area of Science:

• Neuroimaging
• Pediatric Epilepsy Surgery

Background:

• Functional MRI (fMRI) is crucial for identifying eloquent cortex to preserve function during epilepsy surgery.
• Pediatric fMRI language and memory tasks are effective even in clinically complex children.
• Existing pediatric fMRI studies predominantly focus on monolingual English speakers, overlooking the growing prevalence of other languages (LOEs) in diverse populations.

Purpose of the Study:

• To evaluate the efficacy of pediatric fMRI for bilingual patients with LOEs undergoing epilepsy surgery workups.
• To compare language activation in bilingual patients using both their native LOE and English.
• To assess the concordance of language representation in the brain for epilepsy surgery planning.

Main Methods:

• Retrospective review of epilepsy surgery workup patients at Seattle Children's Hospital (2007-2021).
• Identification of patients with valid verbal fluency fMRI tasks, including bilingual and LOE patients.
• Comparison of LOE versus English fMRI activation in bilingual patients, focusing on Broca's and Wernicke's areas.

Main Results:

• Out of 363 patients, 63 (17%) were bilingual or LOE-only.
• 16 of 18 bilingual patients with LOE and English scans showed reliable language region of interest (ROI) activation.
• All patients demonstrated activation in both languages, with high concordance (100% Broca's, 94% Wernicke's) in laterality, though activation extent varied.

Conclusions:

• Pediatric fMRI language tasks are effective for bilingual patients undergoing epilepsy surgery evaluation.
• Language fMRI activations in LOE and English were generally concordant in laterality for individual patients.
• Larger sample sizes, improved bilingual proficiency assessment, and standardized fMRI protocols are needed for diverse pediatric populations.