Is Hippocampal Damage in Extratemporal Epilepsy Seizure Related?
Abstract number :
2.039
Submission category :
Year :
2001
Submission ID :
3116
Source :
www.aesnet.org
Presentation date :
12/1/2001 12:00:00 AM
Published date :
Dec 1, 2001, 06:00 AM
Authors :
H. Cross, PhD MRCP, Neurosciences, Institute of Child Health, UCL, London, United Kingdom; B. Harding, FRCPath, Neuropathology, Great Ormond Street Hospital for Children NHS Trus, London, United Kingdom; W. Harkness, FRCS, Neurosurgery, Great Ormond Stree
RATIONALE: Hippocampal sclerosis may be seen in isolation or in association with other pathologies. The underlying cause to this pathology, and the relationship to antecedent events remains under debate. This study reviews the clinical parameters of children undergoing resective surgery for extratemporal epilepsy, with and without apparent hippocampal damage, to determine possible causal factors.
METHODS: Clinical and pathological data were reviewed of 28 children with extratemporal epilepsy who underwent resective surgery (including the hippocampus) as part of their management. Twenty six underwent hemispherectomy and two multilobar resection. Three main groups were distinguished; those with typical mesial temporal sclerosis (Group 1 MTS, N=11), those with hippocampal damage not recognised as MTS (Group 2, N=9), and those with no hippocampal damage (Group 3, N=8). Only 3 children had definite evidence of temporal lobe seizures; 2 in group 1 and one in group3.
RESULTS: No difference was seen between the groups with regard to age of surgery , duration of epilepsy or seizure frequency; however group 3 had a significantly lower age of onset of seizures (mean 1.6m) compared to group 2 (mean 25m) or group 3 (mean 30m). Ischaemic pathology was more prevalent amongst group 1 (7/11 patients) as compared to groups 2 & 3 (3/9 & 2/8) and developmental pathology in groups 2 &3 (5/9 & 5/8) compared to group 1 (2/11). A history of status epilepticus was found in an equal number of children in the three groups (2,2 &3 resectively); 4 children had a history of febrile convulsion (one from group1 and 3 from group 2).
CONCLUSIONS: The higher prevalence of ischaemic damage amongst children with MTS in this series may suggest that underlying aetiology may influence the development of hippocampal damage. However, the most striking results appear to be the younger age of onset of epilepsy in the group with no hippocampal abnormality with no differences seen in age at onset of surgery, duration of epilepsy or frequency of seizures. This may suggest a possible protective affect of seizures starting early in the first year of life.