Different presurgical characteristics and seizure outcomes in children with focal cortical dysplasia type I or II.
OBJECTIVE
Cortical dysplasia (FCD) is a frequent cause of epilepsy in childhood. Two major pathological variants are distinguished, FCD type I and II. The aim of the study was to characterize differences between FCD type I and II with respect to imaging and EEG findings, clinical and neuropsychological presentations, and surgical outcome.


METHODS
Forty children with refractory epilepsy and histopathologically confirmed FCD were retrospectively analyzed. FCD type I was identified in 24 and FCD type II in 16 patients.


RESULTS
Characteristic MRI abnormalities in FCD type I included subtle white matter signal changes and regional reduction of the white matter volume. Typical MRI findings in FCD type II were increased cortical thickness, transmantle sign, gray-white matter junction blurring, fluid-attenuated inversion recovery (FLAIR) and proton density (PD) gray matter signal changes as well as T1w, and PD white matter signal changes. Continuous EEG slowing was significantly more common in patients with FCD type I. Children with FCD type I presented with lower levels of intelligence and were suffering more often from maladaptive behavior and behavioral disorders. Surgical outcome was significantly worse in the FCD type I group (seizure freedom was achieved in 21% FCD type I patients and in 75% FCD type II subjects, p < 0.001).


CONCLUSIONS
Clinically important differences were found in children with distinct histopathological subtypes of FCD. Due to prominent neuropsychological deficits and worse seizure outcome, treatment strategies in FCD type I are more challenging than previously reported and these children should be recognized and specifically addressed within the incoherent group of patients with malformative brain disorders.
Krsek
Pavel
P
Department of Pediatric Neurology, Charles University, Second Medical School, Motol Hospital, Prague, Czech Republic. pavel.krsek@post.cz
Pieper
Tom
T
Karlmeier
Anja
A
Hildebrandt
Michelle
M
Kolodziejczyk
Dieter
D
Winkler
Peter
P
Pauli
Elisabeth
E
Blümcke
Ingmar
I
Holthausen
Hans
H
D017668:Age of Onset; D000911:Antibodies, Monoclonal / Q000378:metabolism; D001284:Atrophy / Q000473:pathology; D002648:Child; D004569:Electroencephalography; D005260:Female; D019788:Fluorodeoxyglucose F18; D005904:Glial Fibrillary Acidic Protein / Q000378:metabolism; D006624:Hippocampus / Q000473:pathology; D006801:Humans; D007150:Immunohistochemistry; D008279:Magnetic Resonance Imaging; D008297:Male; D054220:Malformations of Cortical Development / Q000453:epidemiology* / Q000378:metabolism / Q000473:pathology*; D011182:Postoperative Care; D011300:Preoperative Care; D019275:Radiopharmaceuticals; D012189:Retrospective Studies; D012640:Seizures / Q000453:epidemiology* / Q000601:surgery*; D016896:Treatment Outcome
D000911:Antibodies, Monoclonal; D005904:Glial Fibrillary Acidic Protein; D019275:Radiopharmaceuticals; D019788:Fluorodeoxyglucose F18