title: A distinct variant of focal cortical dysplasia type I characterised by magnetic resonance imaging and neuropathological examination in children with severe epilepsies.
abstract: Focal Cortical Dysplasias (FCDs) present with a large clinicopathological spectrum. FCDs are believed to relate directly to an epileptogenic condition, although seizure control by surgical resection is variable. This applies in particular to young children with multilobar FCDs, suffering from severe epilepsies and psychomotor retardation. Herein, we performed a comparative analysis of presurgically available data and microscopic inspection of resected cortical specimens to further characterise the pathomorphological spectrum of FCD. Multilobar resection procedures were performed in a consecutive series of 18 young children (mean 7.6 years) with severe pharmaco-resistant epilepsies following extensive presurgical surface-/invasive video-EEG monitoring intraoperative electro-corticography (iECoG), as well as high resolution MRI. In all cases, systematic neuropathological examination of surgical specimens was performed with respect to architectural abnormalities and cell density measurements. These histomorphological data were compared with volumetric MRI analysis. Histopathological examination revealed increased neuronal densities correlating with decreased cortical thickness and abundance of neuronal microcolumns in all cases. Intriguingly, the affected cerebral hemisphere was significantly smaller, relative to the non-epileptogenic contralateral side, in 16 children of our patient series. In conclusion, hypoplastic neocortex and columnar architectural disorganisation point to compromised cortical development, and appear as distinct FCD I subtype in children suffering from severe epilepsies and psychomotor retardation.
authors.affiliation: Department of Neuropathology, University Hospital, Erlangen, Germany. bluemcke@uk-erlangen.de
authors.forename: Ingmar
authors.initials: I
authors.lastname: Blümcke
authors.forename: Tom
authors.initials: T
authors.lastname: Pieper
authors.forename: Elisabeth
authors.initials: E
authors.lastname: Pauli
authors.forename: Michelle
authors.initials: M
authors.lastname: Hildebrandt
authors.forename: Manfred
authors.initials: M
authors.lastname: Kudernatsch
authors.forename: Peter
authors.initials: P
authors.lastname: Winkler
authors.forename: Anja
authors.initials: A
authors.lastname: Karlmeier
authors.forename: Hans
authors.initials: H
authors.lastname: Holthausen
mesh_terms: D002540:Cerebral Cortex / Q000473:pathology; D002648:Child; D014644:Genetic Variation; D006801:Humans; D007150:Immunohistochemistry; D008279:Magnetic Resonance Imaging / Q000379:methods; D054220:Malformations of Cortical Development / Q000145:classification* / Q000235:genetics / Q000473:pathology