Type I Focal Cortical Dysplasia: Surgical Outcome Is Related to Histopathology

Epileptic Disord. 2010 Sep;12(3):181-91. doi: 10.1684/epd.2010.0327. Epub 2010 Jul 27.

Abstract

Pre-surgical and post-surgical data were examined and compared from 215 consecutive patients undergoing surgery for intractable epilepsy. Patients were selected on the basis of a proven histopathological diagnosis of type I focal cortical dysplasia (FCD I), alone or associated with other lesions. The patients were divided into five sub-groups: i) 66 with isolated FCD I, ii) 76 with FCD I and hippocampal sclerosis, iii) 49 with FCD I and tumours, iv) 16 with FCD I and other malformations of cortical development and v) eight with FCD I and anoxic-ischaemic or inflammatory diseases. The duration of epilepsy was greatest in patients with FCD I associated with hippocampal sclerosis, and those with isolated FCD I showed the highest seizure frequency at the time of surgery. Hippocampal sclerosis and tumours were the most frequent pathological lesions associated with FCD I in temporal lobe epilepsy. Febrile seizures significantly correlated with the presence of hippocampal sclerosis and FCD I. Isolated FCD I was observed in 31% of the patients, characterized by frequent seizures, negative magnetic resonance imaging, and frequent frontal or multilobar involvement. In comparison to patients with FCD I associated with hippocampal sclerosis, MCD or tumours, the patients with isolated FCD I had a worse post-surgical outcome (46% in class I). Our findings indicate that there is a high incidence of FCD I associated with other apparently distinct pathologies, particularly those affecting the temporal lobe, and highlight the need for a comprehensive clinicopathological approach for the classification of FCD I.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adolescent
  • Age of Onset
  • Brain / pathology
  • Cerebral Cortex / anatomy & histology
  • Cerebral Cortex / pathology
  • Child
  • Child, Preschool
  • Electroencephalography
  • Epilepsy / pathology
  • Epilepsy / surgery
  • Humans
  • Magnetic Resonance Imaging / methods
  • Malformations of Cortical Development / classification
  • Malformations of Cortical Development / pathology*
  • Malformations of Cortical Development / surgery*
  • Neurons / pathology
  • Reference Values
  • Treatment Outcome