Neuroimaging in Children With Inherited Metabolic Epilepsies

Inherited metabolic epilepsies (IMEs) represent inherited metabolic disorders in which seizures, various in types and typically intractable, are one of the predominant manifestations and primary determinants of the overall outcome. A metabolic etiology should be suspected in any case of refractory seizures stemming from an undetermined cause. While the occurrence rate of individual IMEs is rare, their cumulative prevalence is high enough to pose a significant clinical challenge. Concurrently with genetic and metabolic tests, neuroimaging is considered part of the first tier of their investigation, attained with an aim to affirm or counter the phenotype. It may be normal or nonspecific; however, as described by this overview, there is an appreciable number of IMEs associated with distinct MRI or magnetic resonance spectroscopy patterns. Apart from narrowing or supporting their diagnoses, these neuroimaging patterns may serve as biomarkers to monitor treatment efficacy and outcome. Other advanced modalities and techniques, such as PET, fMRI, diffusion tensor imaging, MRI g-ratio mapping, and functional near-infrared spectroscopy, broaden our insights relating to their pathophysiology, clinical course, targeted treatment development, and prognosis.