Magnetic resonance imaging abnormalities in the resection region correlate with histopathological type, gliosis extent, and postoperative outcome in pediatric cortical dysplasia

Abstract

<jats:sec> <jats:title>Object</jats:title> <jats:p>The authors conducted a study to correlate histopathological features, MRI findings, and postsurgical outcomes in children with cortical dysplasia (CD) by performing a novel resection site–specific evaluation.</jats:p></jats:sec> <jats:sec> <jats:title>Methods</jats:title> <jats:p>The study cohort comprised 43 children with intractable epilepsy and CD. The MR image review was blinded to pathology but with knowledge of the resection location. An MRI score (range 0–7) was calculated for each resection region based on the number of imaging features of CD and was classified as “lesional” or “nonlesional” according to all imaging features. Outcome was determined using the International League Against Epilepsy (ILAE) scale. The determination of pathological CD type was based on the ILAE 2011 consensus classification system, and the cortical gliosis pattern was assessed on GFAP staining.</jats:p></jats:sec> <jats:sec> <jats:title>Results</jats:title> <jats:p>There were 89 resection regions (50 ILAE Type I, 29 Type IIa, and 10 Type IIb). Eleven (25.6%) of 43 children had more than one type of CD. The authors observed MRI abnormalities in 63% of patients, characteristic enough to direct resection (lesional) in 42%. Most MRI features, MRI score ≥ 3, and lesional abnormalities were more common in patients with Type II CD. Increased cortical signal was more common in those with Type IIb (70%) rather than Type IIa (17.2%) CD (p = 0.004). A good outcome was demonstrated in 39% of children with Type I CD and 72% of those with Type II CD (61% in Type IIa and 100% in Type IIb) (p = 0.03). A lesional MRI abnormality and an MRI score greater than 3 correlated with good outcome in 78% and 90% of patients, respectively (p &lt; 0.03). Diffuse cortical gliosis was more prevalent in Type II CD and in resection regions exhibiting MRI abnormalities. Complete surgical exclusion of the MRI abnormality was associated with a better postoperative outcome.</jats:p></jats:sec> <jats:sec> <jats:title>Conclusions</jats:title> <jats:p>This study provides a detailed correlation of MRI findings, neuropathological features, and outcomes in children with intractable epilepsy by using a novel resection site–specific evaluation. Because 25% of the patients had multiple CD subtypes, a regional analysis approach was mandated. Those children with lesional MRI abnormalities, Type II CD, and surgical exclusion of the MRI abnormality had better outcomes. Type II CD is more detectable by MRI than other types, partly because of the greater extent of associated gliosis in Type II. Although MRI findings were correlated with the pathological CD type and outcome in this study, the majority of patients (58%) did not have MRI findings that could direct surgical therapy, underscoring the need for improved MRI techniques for detection and for the continued use of multimodal evaluation methods in patient selection.</jats:p></jats:sec>

Cytochrome c oxidase deficit is associated with the seizure onset zone in young patients with focal cortical dysplasia Type II

“…In brief, the standard presurgical evaluation included detailed history and clinical examination, scalp video-EEG monitoring, MRI, 2-[ 18 F]fluoro-2-deoxy-D-glucose positron emission tomography (FDG-PET), ictal/ interictal single photon emission computed tomography (SPECT), and magnetoencephalography/magnetic source imaging (MEG/MSI). Protocols for neuroimaging methods have been published previously (Leach et al 2014). Ictal EEG and high quality MRI were uniformly obtained.…”

Mesial temporal lobe morphology in intractable pediatric epilepsy: so-called hippocampal malrotation, associated findings, and relevance to presurgical assessment

“…30 All subjects underwent imaging following a dedicated seizure protocol MRI, as detailed elsewhere. 23,30 Forty-four patients underwent imaging at 3 T and 4 patients at 1.5 T using 1-mm (n = 46) or 1.25-mm (n = 2) isotropic T1-weighted sequences, and 1-mm isotropic T2-weighted FLAIR volumetric sequences (n = 41). A matched control group of 48 healthy children was obtained using Cincinnati MR Imaging of NeuroDevelopment (C-MIND) study group subjects who underwent MRI at our institution.…”

“…HIMAL was not used as a lateralizing lesional finding for epilepsy surgery. 23 The control population was matched as closely as was feasible with the study population with regard to age, sex, and handedness. Resection and pathological analysis were performed as described elsewhere.…”

“…Resection and pathological analysis were performed as described elsewhere. 23 Pathological classification used the 2011 International League Against Epilepsy (ILAE) classification system for cortical dysplasia. 6 To assess the various morphological features and measurements of the temporal lobe, volumetric 3D T1-weighted and T2-weighted FLAIR data sets were analyzed in a clinical picture archiving and communication system (PACS) environment with multiplanar reformation capabilities (Merge PACS, Merge Healthcare).…”

Oncology imaging: Diagnosis

“…MRI is able to show abnormalities in the majority of Type II dysplasias but only in some of the Type I cortical dysplasias although, in practice, it may be possible to distinguish between Type I and Type II. 7 The typical appearance of FCD Type IIB (with balloon cells) is a band of hyperintensity on T2-weighted and FLAIR images extending from the gray and white matter interface to the surface of the ventricles (Figure 2). To visualise this often subtle finding, multiplanar thin-section images should be performed.…”