Peri-ictal magnetic resonance imaging findings in pediatric seizures: a scoping review on pearls and pitfalls from a heterogeneous population.

Background: Peri-ictal magnetic resonance imaging (MRI) brain abnormalities are increasingly recognized, yet their temporal evolution and imaging features in children remain incompletely characterized. This scoping review aims to map and synthesize two decades of evidence on MRI-based seizure-related changes in pediatric patients, providing an overview of the existing literature, reported imaging findings, diagnostic challenges, and knowledge gaps. Methods: PubMed and MEDLINE databases were searched (January 2000 to September 2025) for studies evaluating MRI changes in focal seizures (FS), prolonged febrile seizures (PFS), or status epilepticus (SE) in children aged 0-18 years. Studies reporting diffusion weighted images/apparent diffusion coefficient maps (DWI/ADC), T2/fluid attenuated inversion recovery (FLAIR), arterial spin labelling (ASL), functional MRI (fMRI), or diffusion tensor imaging (DTI) changes were considered. Results: Twenty-seven studies were included, most focusing on children with PFS and SE, whereas focal seizures were underreported, particularly extratemporal ones. Acute MRI findings (<1-week) most commonly showed hippocampal or limbic swelling with T2/FLAIR hyperintensity and diffusion restriction, consistent with edema, particularly following prolonged seizures. ASL reported cases of early focal hyperperfusion concordant with the seizure focus, often persisting longer than diffusion abnormalities. Subacute changes (days 4-10) included evolving edema and post-ictal hypoperfusion, while chronic findings included hippocampal atrophy, mesial temporal sclerosis (MTS), and persistent white matter abnormalities on DTI. Thalamic, basal ganglia, and subcortical white matter involvement have been hypothesized to reflect excitotoxic or inflammatory propagation beyond the seizure onset zone. Early DWI/ADC changes correlated with seizure duration, and when involving the hippocampus predicted MTS and long-term cognitive sequelae in some studies. Conclusions: Peri-ictal MRI abnormalities in children are most frequently described in PFS and SE, where recurring patterns of acute edema and later structural changes have been reported. However, existing evidence is heterogeneous and weighted toward early-life and acute symptomatic populations, limiting generalizability. Associations between early imaging changes and longer-term outcomes remain inconsistent. Advanced imaging techniques, largely underreported, may provide additional insights into seizure-related network alterations, although their prognostic relevance remains uncertain. Overall, larger, seizure-type specific longitudinal studies are needed before definitive conclusions can be made.