Relationship of hippocampal sclerosis to duration and age of onset of epilepsy, and childhood febrile seizures in temporal lobectomy patients

Epilepsy Res. 1996 Jun;24(2):119-26. doi: 10.1016/0920-1211(96)00008-3.

Abstract

Controversy exists as to whether hippocampal sclerosis (HS) is a preexisting cause or a consequence of seizures. We investigated 122 consecutive patients who underwent anterior temporal lobectomy for intractable epilepsy between 1989 and 1992. MRI scans were normal apart from evidence of HS in 5 cases. The degree of HS was graded from 0 to 4. There was a significant inverse correlation between age of seizure onset and grade of HS (P < 0.0001), and a positive correlation between duration of epilepsy and grade of HS (P < 0.001). Using a dichotomous grouping of HS (HPSC - for grades 0 and 1 [no/mild HS], and HPSC + for grades 3 and 4 [moderate/marked HS]), there was a positive correlation between HPSC + and a history of childhood febrile seizures (CFS) (P = 0.003), earlier age of onset of epilepsy (P < 0.001) and longer duration of epilepsy (P < 0.001). There was no correlation with history of particularly prolonged individual seizures. Partial correlations after controlling for age at onset of epilepsy showed that there was no longer a significant relationship between HPSC + and duration of epilepsy. After controlling for duration of epilepsy, the relationship between HPSC + and age of onset remained significant (P < 0.001). The correlation between HPSC + and CFS, controlling for age at onset, was not significant. A series of logistic regression analyses showed age at onset to be the only predictor of HPSC +. It is concluded that this is supportive evidence for preexisting HS being a cause of temporal lobe epilepsy and not a consequence of seizures.

Publication types

  • Clinical Trial

MeSH terms

  • Adult
  • Age of Onset
  • Child
  • Electroencephalography
  • Epilepsy / physiopathology*
  • Female
  • Hippocampus / pathology*
  • Hippocampus / physiopathology
  • Humans
  • Magnetic Resonance Imaging
  • Male
  • Regression Analysis
  • Sclerosis
  • Seizures, Febrile / physiopathology*
  • Temporal Lobe / physiology*
  • Temporal Lobe / surgery
  • Treatment Outcome