Purpose or Case Report: Neuroimaging plays a vital role in the diagnosis of epileptogenic foci and directing subsequent ongoing multi-disciplinary team approach pathways in paediatric epilepsy. Our centre is one of four tertiary level paediatric epilepsy surgery centres in England & Wales. The different epileptogenic pathologies can have similar imaging features and this educational review discusses the typical MRI findings of the commonly encountered epileptogenic foci in the paediatric population with an emphasis on advanced MRI features looking to demonstrate further typical patterns in our cohort which can help in cases of diagnostic uncertainty.
Methods & Materials: Between November 2015 and March 2023 a total of 82 patients went forward for neurosurgery after going through our paediatric epilepsy MDT pathway. All patients had resected lesion histology performed and this was retrospectively correlated with the most recent complete MRI study using our departmental MRI epilepsy protocol (and any previous MRI studies) to confirm if a radiological primary and / or differential diagnosis was given at the time of report and the degree of radiological-histological correlation.
Results: Histology proven brain tumours in our cohort included Ganglioglioma WHO Grade 1, Dysembryoplastic neuroepithelial tumours (DNET), Hypothalamic hamartomas, Oligodendroglioma WHO Grade 1, Pleomorphic xanthoastrocytoma WHO Grade 2, Gangliocytoma WHO Grade 1, Cavernoma and Focal Cortical Dysplasia (FCD) type 1a, Ib, IIa, IIb and of undetermined classification. The MRI imaging findings of each pathology are discussed in detail, along with advanced MRI techniques such as spectroscopy and MR perfusion when performed and where there has been concordance in these appearances between patients with the same histologically proven lesions.
Conclusions: This educational review demonstrates the important role the radiologist has in the surgical management of patients in this often medically complex group. This educational review will help identify and characterise paediatric epileptogenic lesions that range from subtle FCD to large tumours. This review also emphasises the role of advanced MRI in differentiating pathology and in problem solving.