Authors :
Presenting Author: Hua Xie, PhD – Children's National Hospital
Venkata Sita Priyanka Illapani, MS – Children’s National Hospital; Louis Gilbert Vezina, MD – Children’s National Hospital; Taha Gholipour, MD – George Washington University Epilepsy Center; Chima Oluigbo, MD – Children’s National Hospital; William Gaillard, MD – Children’s National Hospital; Nathan Cohen, MD – Children's National Hospital
Rationale:
Focal cortical dysplasia (FCD) is the most common cause of surgically-remediable pharmacoresistant epilepsy (PRE) in children. There is mounting evidence of the network basis of focal epilepsy. The brain can be segmented into functional networks that can be identified by resting-state functional MRI. We hypothesized that FCDs causing pharmacoresistant epilepsy would have increased intra-network and decreased inter-network connectivity.
Methods:
Patients were selected retrospectively from the epilepsy surgery database at Children’s National Hospital in Washington, DC. Inclusion criteria were: 3T MRI-confirmed FCD from January 2011 to January 2021; resting state fMRI done at ages five to 22 years at MRI; at least 18 months of documented follow-up after MRI. Records were excluded if there was dual pathology (except for mesial temporal sclerosis), hemimegalencephaly, or tuberous sclerosis complex present in imaging or history. Seed-based (FCDs as seeds) functional connectivity analysis was performed and whole-brain connectivity maps were generated from healthy controls (HC). Z-scored patient whole-brain connectivity maps were generated using HC as a reference. One-sample t-test was used to control for age, gender, lesion size. Yeo 7-network map used to determine FCD dominant network and compare average intra-network and inter-network connectivity
Results:
Twenty-one FCD patients with PRE and 14 healthy controls were included. Whole brain connectivity mapping showed decreased group-level connectivity in the angular gyrus, inferior frontal gyrus, and mesial prefrontal cortices (Figure 1). There is decreased intra-network compared to inter-network connectivity in patients with FCD-PRE, p< 0.001, clusterwise corrected with p < 0.05.