Abstracts

Evidence of Language Network Reorganization and Compromised Language Function in Pediatric Patients with Focal Refractory Epilepsy

Abstract number : 2.466
Submission category : 5. Neuro Imaging / 5B. Functional Imaging
Year : 2023
Submission ID : 1353
Source : www.aesnet.org
Presentation date : 12/3/2023 12:00:00 AM
Published date :

Authors :
Presenting Author: Alena Hornak, BA – Boston Children's Hospital

Dana Martino, Bachelors of Science – Research Assistant, Psychiatry, Boston Children's Hospital; Clemente Vega, Doctor of Psychology,ABPP-CN – Attending Neuropsychologist, Neurology, Boston Children's Hospital; Katrina Boyer, Doctor of Philosophy – Neuropsychologist, Neurology, Boston Children's Hospital; Ralph Suarez, Doctor of Philosophy – Research Associate, Radiology, Boston Children's Hospital; Phillip Pearl, Doctor of Medicine – Director of Epilepsy and Clinical Neurophysiology, Neurology, Boston Children's Hospital; Simon Warfield, Doctor of Philosophy – Director of Radiology Research, Radiology, Boston Children's Hospital; Alyssa Ailion, Doctor of Philosophy – Attending Neuropsychologist, Neurology, Boston Children's Hospital

Rationale:
Patients with focal refractory frontal or temporal lobe epilepsy are at the highest risk for epileptic zone overlap with language eloquent cortex, and atypical language reorganization is more common. The functional impact of brain reorganization is unclear given the long-term impacts of surgical interventions at a young age. Reorganization can be a positive prognostic indicator of functional resilience; however, it may indicate compromised neural networks or developmental persistence resulting in poorer function. As such, we examined the relationship of brain reorganization and language-based neuropsychological function to advance our understanding of brain network organization and function.

Methods:
We reviewed 26 patients with focal temporal (n=13) or frontal (n=13) epilepsy with Phase I Surgical Evaluation including a fMRI and Neuropsychological Assessment at Boston Children’s Hospital. Language activation was contrasted against a control task in the frontal and temporal regions and language laterality indices(LI) were calculated. Participants were categorized as evidence of reorganization (Left seizure onset zone(SOZ); Right/Bilateral LI; n=8), lacked reorganization(L SOZ,L LI; n=10), typical(R SOZ,L LI; n=4) or atypical language representation (R SOZ, R/Bilateral LI; n=4). Neuropsychological measures included age-appropriate Wechsler IQ measure, Boston Naming Test(BNT) and Verbal Fluency from the Delis-Kaplan Executive Function System(DKEFS).

Results:
Participants with evidence of reorganization(M=4.46, SD±3.61) had a younger age of onset than the atypical(M=9.25, SD±3.84; p=.05) and typical(M=13.54, SD±2.47; p< .001) groups. One-way ANOVA, post-hoc Fisher’s Least Significant Difference indicated that those who lacked reorganization(SS=103) had higher perceptual and fluid reasoning than those who reorganized(SS=82; p=.02), and slightly lower scores than the typical(SS=88) or atypical (SS=99) groups. Those that lacked reorganization(SS=7) and those that reorganized(SS=6) had lower category fluency than the typical group(SS=11) which approached significance(p=.07). Overall FSIQ was not statistically different but clinically different(lacked SS=94; reorganized SS=78; typical SS=85; atypical SS=88), however this was driven by subscale differences other than verbal reasoning, which was similar across groups(lacked SS=99; reorganized SS=95; typical SS=98; atypical SS=97). BNT was lowest in the reorganized(SS=70) and atypical(SS=76) groups, followed by lack of reorganization(SS=77), and typical groups(SS=105).
Neuro Imaging