title: Heterotopia associated with hippocampal sclerosis: an under-recognized cause of early onset epilepsy in children operated on for temporal lobe epilepsy.
abstract: OBJECTIVE
  The aim of this study is to report on 52 children operated on for pharmacoresistant temporal lobe epilepsy, with special emphasis on histopathology and correlation with clinical features.
  
  
  METHODS
  Charts were retrospectively analyzed. All children underwent comprehensive clinical, electrophysiological and radiological investigations before surgery. Surgical procedures were tailored according to scalp, foramen ovale and eventually depth electrode recordings. Histopathology was compared with clinical variables (χ (2) and Fisher's exact tests). Outcome was evaluated using the Engel scale.
  
  
  RESULTS
  Developmental tumor was found in 14 cases, malformation of cortical development (MCD) in 26, isolated hippocampal sclerosis (HS) in 5 and gliosis in 7. Dual pathology (DP) affected 18 patients and the main extrahippocampal lesion consisted of microscopic sub-cortical heterotopias (HS-HT) for 15 patients who shared a particular clinical pattern: a history of febrile seizures (FS) and/or brain injury, early onset of epilepsy without latent period from FS to the first temporal seizure, and a particularly good outcome following surgery.
  
  
  CONCLUSIONS
  In our pediatric temporal lobe surgery series, the prevalence for MCD and for DP was higher than in adult series. Age at seizure onset depends on pathology, and is earlier when involving the neocortex rather than only the hippocampus. We identify the association HS-HT (the most frequent DP in this series), with particular clinical features.
authors.affiliation: Unité de Neurophysiologie-Service Explorations Fonctionnelles, Hôpital Robert Debré, APHP, 48 Boulevard Serrurier, Paris, France. elisa.lopez@rdb.aphp.fr
authors.forename: E
authors.initials: E
authors.lastname: López H
authors.forename: M
authors.initials: M
authors.lastname: Fohlen
authors.forename: A
authors.initials: A
authors.lastname: Lelouch-Tubiana
authors.forename: O
authors.initials: O
authors.lastname: Robain
authors.forename: C
authors.initials: C
authors.lastname: Jalin
authors.forename: C
authors.initials: C
authors.lastname: Bulteau
authors.forename: G
authors.initials: G
authors.lastname: Dorfmüller
authors.forename: O
authors.initials: O
authors.lastname: Dulac
authors.forename: O
authors.initials: O
authors.lastname: Delalande
mesh_terms: D017668:Age of Onset; D001930:Brain Injuries / Q000150:complications; D001932:Brain Neoplasms / Q000150:complications; D002648:Child; D054221:Classical Lissencephalies and Subcortical Band Heterotopias / Q000150:complications; D004569:Electroencephalography; D004833:Epilepsy, Temporal Lobe / Q000209:etiology* / Q000473:pathology / Q000503:physiopathology / Q000601:surgery*; D005260:Female; D005500:Follow-Up Studies; D005911:Gliosis / Q000209:etiology; D006624:Hippocampus / Q000473:pathology*; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D054220:Malformations of Cortical Development / Q000150:complications; D019635:Neurosurgical Procedures / Q000379:methods; D012189:Retrospective Studies; D012598:Sclerosis / Q000209:etiology; D003294:Seizures, Febrile / Q000209:etiology / Q000473:pathology / Q000503:physiopathology; D013702:Temporal Lobe / Q000473:pathology / Q000503:physiopathology / Q000601:surgery*; D016896:Treatment Outcome