title: Magnetic resonance imaging evidence of hippocampal sclerosis in asymptomatic, first-degree relatives of patients with familial mesial temporal lobe epilepsy.
abstract: OBJECTIVE
  To investigate the presence of hippocampal atrophy (HA) and other magnetic resonance imaging (MRI) signs of hippocampal sclerosis (HS) in asymptomatic relatives of patients with familial mesial temporal lobe epilepsy (FMTLE).
  
  
  METHODS
  We invited first-degree, asymptomatic relatives of patients with FMTLE to participate in our MRI protocol. After obtaining informed consent, all participating individuals underwent an MRI examination. Hippocampal abnormality was determined by qualitative and volumetric analyses, using a standard protocol.
  
  
  RESULTS
  We studied 52 asymptomatic individuals (27 men), with a mean age of 32 years (range, 7-71 years), from 11 families with FMTLE. Volumetric studies showed HA in 18 (34%) of 52 individuals: 11 had left HA and 7 had bilateral HA. In addition, careful visual analysis of T1- and T2-weighted images showed additional classic MRI signs of HS (such as abnormal T2 signal and/or abnormal internal structure) in 14 of these 18 individuals. There was no age difference between individuals with and without HA (t test, P =.80).
  
  
  CONCLUSIONS
  Our findings indicate that MRI evidence of HS is not necessarily related to seizure severity and may occur in individuals who never had seizures. In addition, these observations strongly indicate that HS in FMTLE is not a consequence of recurrent seizures and is determined by a strong genetic predisposition. The determination of seizure severity in patients with FMTLE probably depends on the interaction of different factors, both genetic and environmental.
authors.affiliation: Department of Neurology, University of Campinas, São Paulo, Brazil.
authors.forename: Eliane
authors.initials: E
authors.lastname: Kobayashi
authors.forename: Li M
authors.initials: LM
authors.lastname: Li
authors.forename: Iscia
authors.initials: I
authors.lastname: Lopes-Cendes
authors.forename: Fernando
authors.initials: F
authors.lastname: Cendes
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D002648:Child; D004833:Epilepsy, Temporal Lobe / Q000235:genetics* / Q000473:pathology*; D005190:Family; D005260:Female; D006624:Hippocampus / Q000473:pathology*; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods / Q000706:statistics & numerical data; D008297:Male; D008875:Middle Aged; D010361:Patients / Q000706:statistics & numerical data; D012598:Sclerosis