Authors :
Presenting Author: Giovanna Stefanini, BS – Boston Children's Hospital
Dana Martino, BS – Boston Children's Hospital
Jack O'keeffe Donohue, MD – Boston Children's Hospital
Scellig Stone, MD, PhD – Boston Childrens Hospital & Harvard Medical School
Phillip Pearl, MD – Boston Children's Hospital & Harvard Medical School
Jurriaan Peters, MD PhD – Boston Children's Hospital
Simon Warfield, PhD – Boston Children's Hospital & Harvard Medical School
Aaron Warren, PhD – Boston Children's Hospital & Mass General Hospital
Alyssa Ailion, PhD – Boston Children's Hospital & Harvard Medical School
Rationale:
Patients with drug refractory epilepsy (DRE) who undergo corpus callosotomy often present with diverse presurgical neurocognitive and clinical profiles. The corpus callosum (CC) is essential for interhemispheric communication, and has been implicated in cognitive and language functioning (Hinckley et al., 2016; Moser et al., 2024). This study investigates the relationships between structural MRI-derived volumes and presurgical cognitive function in a corpus callosotomy cohort. We hypothesized a positive relationship between CC volume and better baseline cognitive/language functioning. We also explore how demographic, and seizure related factors are associated with presurgical CC volumes.
Methods:
We retrospectively reviewed 21 presurgical CC candidates who underwent neuropsychological evaluation at Boston Children’s Hospital. Cognitive measures included IQ tests (WISC, WPPSI, WAIS, DAS) and verbal fluency (NEPSY, DKEFS). T1-weighted images were processed using FreeSurfer’s recon-all pipeline to extract CC volume and subsections. We used publicly available datasets to create age-matched population norms for the volume of the corpus callosum. We used these mean and standard deviation values based on age to generate z-score values for volume of the corpus callosum in our clinical population. Correlations were computed between demographic/medical factors, CC volumes, IQ, and verbal fluency.
Results:
Analyses conducted using SPSS (v27) revealed several significant associations. Average CC volumes and Z-scores were calculated (mm³): posterior (μ=92.6, z=-6.31), mid-posterior (μ=87.1, z=-4.81), central (μ=88.8, z=-4.11), anterior-central (μ=89.7, z=-3.57) , anterior (μ=94.8, z=-6.78), total (μ=453.0, z=-4.79). Conversely, the presence of atypical absence seizures was negatively associated with nonverbal baseline function (r = -0.475, p = 0.030). Total corpus callosum volume was also negatively associated with nonverbal baseline function (r = -0.475, p = 0.030). Additionally, lower central CC volume Z-scores were associated with older age at the time of surgery (r = -0.534, p = 0.040).
Conclusions:
We investigated the relationship between CC volume and cognitive/language function in callosotomy candidates. While CC volume was not associated with neuropsychological measures, it was associated with other measures of baseline functioning (verbality). Since our cohort was lower functioning, we suspect that there was a floor effect on neuropsychological measurement, and this more qualitative indicator of patient functioning was more sensitive to variability in the CC cohort. These findings highlight the need for more nuanced and sensitive neuropsychological tools.
Funding: n/a