Agenesis of the arcuate fasciculi in congenital bilateral perisylvian syndrome: a diffusion tensor imaging and tractography study

Abstract

Objective: To describe the absence of the arcuate fasciculi in 2 cases of congenital bilateral perisylvian syndrome (CBPS).

Design: Case series.

Setting: Pediatric referral hospital-based study.

Patients: Two patients with CBPS, referred to our institution as candidates for surgical treatment of epilepsy. Intervention Diffusion tensor imaging (1.5-T scanner; 15 encoding directions; b = 800 s/mm(2)) and deterministic tractography of the main projection and association tracts.

Main outcome measures: Neuropsychology evaluation; fractional anisotropy, apparent diffusion coefficients, and anatomical aspect of the tracts.

Results: Absence of the arcuate fasciculus was observed in both subjects. Ancillary findings were complete absence of the superior longitudinal fasciculi in 1 case and underdevelopment in the other. Low fractional anisotropy of the left inferior occipitofrontal fasciculus was found in both cases. The same tract was maloriented in 1 of the cases.

Conclusion: Agenesis of the arcuate fasciculus may accompany CBPS.