title: Hippocampal sclerosis in severe myoclonic epilepsy in infancy: a retrospective MRI study.
abstract: OBJECTIVE
  Severe myoclonic epilepsy in infancy (SMEI; Dravet's syndrome) is a malignant epilepsy syndrome characterized by early prolonged febrile convulsions (PFCs) with secondary psychomotor delay and a variety of therapy-resistant seizures. Although the initial symptoms are repeated PFCs, the MRI performed at the onset of disease shows no hippocampal structural abnormalities. We aimed to assess clinical and serial MRI data of patients with SMEI with a special attention to the temporomedial structures. To our knowledge, this is the first systematic MRI study in this disease.
  
  
  METHODS
  Clinical and MRI data of all SMEI patients treated in our hospitals between 1996 and 2004 were reviewed.
  
  
  RESULTS
  Twenty-eight MRIs from 14 children (one to four images/patient) were included. Age at disease onset was between 3 and 9 months; age at initial MRI was 5 months to 13 years. Ten of 14 patients showed hippocampal sclerosis (HS) during the course of the disease (nine unilateral, one bilateral). Six of these 10 had a normal initial MRI. Age at the first verified HS was between 14 months and 13 years. Neither complex partial seizures nor anterior temporal irritative zone was recorded in these children.
  
  
  CONCLUSIONS
  After initially normal structures, in most patients with SMEI, HS develops several months or years after the first PFC. These data support the hypothesis that PFC might be responsible for HS, but other factors and individual sensitivity should play a role in this process.
authors.affiliation: Epilepsy Center, Bethesda Children's Hospital, Budapest, Hungary.
authors.forename: Zsuzsanna
authors.initials: Z
authors.lastname: Siegler
authors.forename: Peter
authors.initials: P
authors.lastname: Barsi
authors.forename: Magdolna
authors.initials: M
authors.lastname: Neuwirth
authors.forename: Judit
authors.initials: J
authors.lastname: Jerney
authors.forename: Maria
authors.initials: M
authors.lastname: Kassay
authors.forename: Jozsef
authors.initials: J
authors.lastname: Janszky
authors.forename: Eva
authors.initials: E
authors.lastname: Paraicz
authors.forename: Marta
authors.initials: M
authors.lastname: Hegyi
authors.forename: Andras
authors.initials: A
authors.lastname: Fogarasi
mesh_terms: D000293:Adolescent; D017668:Age of Onset; D002648:Child; D002675:Child, Preschool; D004831:Epilepsies, Myoclonic / Q000175:diagnosis / Q000473:pathology*; D004833:Epilepsy, Temporal Lobe / Q000175:diagnosis; D005260:Female; D005500:Follow-Up Studies; D007839:Functional Laterality; D006624:Hippocampus / Q000473:pathology*; D006801:Humans; D007223:Infant; D008279:Magnetic Resonance Imaging / Q000706:statistics & numerical data*; D008297:Male; D012598:Sclerosis; D003294:Seizures, Febrile / Q000175:diagnosis