Low-grade focal cortical dysplasia is associated with prenatal and perinatal brain injury.
OBJECTIVE
Prenatal and perinatal adverse events are reported to have a pathogenetic role in focal cortical dysplasia (FCD). However, no data are available regarding the prevalence and significance of this association. A cohort of children with significant prenatal and perinatal brain injury and histologically proven mild malformations of cortical development (mMCD) or FCD was analyzed.


METHODS
We retrospectively evaluated a surgical series of 200 patients with histologically confirmed mMCD/FCD. Combined historical and radiologic inclusion criteria were used to identify patients with prenatal and perinatal risk factors. Electroclinical, imaging, neuropsychological, surgical, histopathologic, and seizure outcome data were reviewed.


RESULTS
Prenatal and perinatal insults including severe prematurity, asphyxia, bleeding, hydrocephalus, and stroke occurred in 12.5% of children with mMCD/FCD (n = 25). Their epilepsy was characterized by early seizure onset, high seizure frequency, and absence of seizure control. Patients with significant prenatal and perinatal risk factors had more abnormal neurologic findings, lower intelligence quotient (IQ) scores, and slower background EEG activity than mMCD/FCD subjects without prenatal or perinatal brain injury. MRI evidence of cortical malformations was identified in 74% of patients. Most patients underwent large multilobar resections or hemispherectomies; 54% were seizure-free 2 years after surgery. Histologically "milder" forms of cortical malformations (mMCD and FCD type I) were observed most commonly in our series.


CONCLUSIONS
Surgically remediable low-grade cortical malformations may occur in children with significant prenatally and perinatally acquired encephalopathies and play an important role in the pathogenesis of their epilepsy. Presurgical detection of dysplastic cortex has important practical consequences for surgical planning.
Krsek
Pavel
P
Department of Pediatric Neurology, Charles University, Second Medical School, Motol University Hospital, Prague, Czech Republic.
Jahodova
Alena
A
Maton
Bruno
B
Jayakar
Prasanna
P
Dean
Patricia
P
Korman
Brandon
B
Rey
Gustavo
G
Dunoyer
Catalina
C
Vinters
Harry V
HV
Resnick
Trevor
T
Duchowny
Michael
M
D000293:Adolescent; D000328:Adult; D001921:Brain / Q000473:pathology / Q000601:surgery; D002540:Cerebral Cortex / Q000473:pathology* / Q000601:surgery; D002648:Child; D002675:Child, Preschool; D004569:Electroencephalography; D004828:Epilepsies, Partial / Q000175:diagnosis / Q000473:pathology* / Q000601:surgery*; D005260:Female; D038421:Hemispherectomy / Q000379:methods; D006801:Humans; D007223:Infant; D007361:Intelligence Tests; D008279:Magnetic Resonance Imaging / Q000706:statistics & numerical data; D008297:Male; D054220:Malformations of Cortical Development / Q000175:diagnosis / Q000473:pathology* / Q000601:surgery*; D009483:Neuropsychological Tests; D011247:Pregnancy; D011296:Prenatal Diagnosis; D011300:Preoperative Care / Q000379:methods; D012307:Risk Factors