title: Progression in temporal lobe epilepsy: differential atrophy in mesial temporal structures.
abstract: OBJECTIVE
  To determine the relationship between hippocampal, amygdalar, and entorhinal cortex atrophy and duration of epilepsy, presence of secondary generalized seizures, and prolonged childhood febrile convulsions in patients with pharmacologically intractable temporal lobe epilepsy (TLE).
  
  
  METHODS
  Volumetric MRI of the hippocampus, amygdala, and entorhinal cortex were performed in 86 consecutive patients with TLE and 44 age- and sex-matched healthy control subjects. Linear regression analysis was used to explore the relation between the volumetric measurements and the clinical parameters.
  
  
  RESULTS
  In simple regressions, duration of epilepsy but not age at seizure onset was related to hippocampal (r2 = 0.19, p < 0.001), entorhinal cortex (r2 = 0.11, p = 0.002), and amygdalar (r2 = 0.15, p < 0.001) atrophy ipsilateral to the seizure focus. Prediction of the regression function to time of onset of recurrent seizures (time = 0) resulted in a y intercept of < 0 for the hippocampus and the entorhinal cortex but was not different from 0 for the amygdala. Patients with a positive history of febrile convulsions had smaller hippocampal volumes ipsilateral to the seizure (p < 0.001). No relationship was found between febrile convulsions and entorhinal cortex and amygdalar volumes or between secondary generalization of seizures and any mesial temporal volume.
  
  
  CONCLUSIONS
  Progressive volume loss in the mesial temporal lobe in relation to duration of epilepsy is not limited to the hippocampus but affects the entorhinal cortex and the amygdala.
authors.affiliation: Department of Neurology and Neurosurgery, McGill University, Montreal Neurological Institute and Hospital, Quebec, Canada.
authors.forename: Neda
authors.initials: N
authors.lastname: Bernasconi
authors.forename: Jun
authors.initials: J
authors.lastname: Natsume
authors.forename: Andrea
authors.initials: A
authors.lastname: Bernasconi
mesh_terms: D000293:Adolescent; D000328:Adult; D017668:Age of Onset; D000368:Aged; D000679:Amygdala / Q000473:pathology / Q000503:physiopathology; D001284:Atrophy / Q000453:epidemiology / Q000473:pathology* / Q000503:physiopathology; D015897:Comorbidity; D003430:Cross-Sectional Studies; D018450:Disease Progression; D004569:Electroencephalography / Q000379:methods; D018728:Entorhinal Cortex / Q000473:pathology / Q000503:physiopathology; D004833:Epilepsy, Temporal Lobe / Q000453:epidemiology / Q000473:pathology* / Q000503:physiopathology; D005260:Female; D006624:Hippocampus / Q000473:pathology / Q000503:physiopathology; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D011792:Quebec / Q000453:epidemiology; D012044:Regression Analysis; D003294:Seizures, Febrile / Q000453:epidemiology; D013702:Temporal Lobe / Q000473:pathology* / Q000503:physiopathology