­­In vivo cerebral glucose utilization and metabolic network in dysplasia-related pediatric frontal lobe epilepsy

Abstract

Abstract Objective Previous evidence has indicated that dysplasia-related frontal lobe epilepsy (FLE) may lead to brain-region-scale or lobe-scale metabolic disturbances. However, few studies have demonstrated the impact on whole-brain metabolic networks. This study aimed to investigate the cerebral glucose utilization and networks using [18F]fluorodeoxyglucose ([18F]FDG) positron emission tomography (PET) in pediatric FLE patients with and without focal cortical dysplasia (FCD). Methods [18F]FDG PET imaging was acquired for 57 participants, comprising 19 FLE patients with FCD (FLE-FCD), 19 FLE patients with no lesions (FLE-NL) and 19 controls. PET images were preprocessed using Statistical Parametric Mapping (SPM). Cerebral glucose utilization was derived through SPM analysis for inter-group comparison, and metabolic networks were constructed from correlation matrices of 90 brain regions. Graph theoretical analysis was performed to explore topological alterations. Results Both FLE patient groups exhibited reduced global glucose metabolism and metabolic connectivity compared to controls, with a greater reduction observed in FLE-FCD. Metabolic abnormalities were observed in multiple brain regions, including the frontal, temporal, and parietal lobes, cingulate gyrus, subcortical regions, and thalamus. Both FLE groups showed suboptimal topological organization, characterized by decreased global efficiency and increased modularity. FLE-FCD displayed more pronounced network disruption. Furthermore, FLE patients demonstrated altered modular structures compared to controls, with distinct arrangements between FLE-FCD and FLE-NL. Conclusions This study presents initial evidence of alterations in the cerebral glucose utilization and metabolic network topological properties in FCD-related pediatric FLE patients, offering valuable insights into understanding the disease mechanisms of FCD-related FLE.