title: Low-grade focal cortical dysplasia is associated with prenatal and perinatal brain injury.
abstract: 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.
authors.affiliation: Department of Pediatric Neurology, Charles University, Second Medical School, Motol University Hospital, Prague, Czech Republic.
authors.forename: Pavel
authors.initials: P
authors.lastname: Krsek
authors.forename: Alena
authors.initials: A
authors.lastname: Jahodova
authors.forename: Bruno
authors.initials: B
authors.lastname: Maton
authors.forename: Prasanna
authors.initials: P
authors.lastname: Jayakar
authors.forename: Patricia
authors.initials: P
authors.lastname: Dean
authors.forename: Brandon
authors.initials: B
authors.lastname: Korman
authors.forename: Gustavo
authors.initials: G
authors.lastname: Rey
authors.forename: Catalina
authors.initials: C
authors.lastname: Dunoyer
authors.forename: Harry V
authors.initials: HV
authors.lastname: Vinters
authors.forename: Trevor
authors.initials: T
authors.lastname: Resnick
authors.forename: Michael
authors.initials: M
authors.lastname: Duchowny
mesh_terms: 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