Cerebral damage in epilepsy: a population-based longitudinal quantitative MRI study.
OBJECTIVE
Whether cerebral damage results from epileptic seizures remains a contentious issue. We report on the first longitudinal community-based quantitative magnetic resonance imaging (MRI) study to investigate the effect of seizures on the hippocampus, cerebellum, and neocortex.


METHODS
One hundred seventy-nine patients with epilepsy (66 temporal lobe epilepsy, 51 extratemporal partial epilepsy, and 62 generalized epilepsy) and 90 control subjects underwent two MRI brain scans 3.5 years apart. Automated and manual measurement techniques identified changes in global and regional brain volumes and hippocampal T2 relaxation times.


RESULTS
Baseline hippocampal volumes were significantly reduced in patients with temporal lobe epilepsy and could be attributed to an antecedent neurologic insult. Rates of hippocampal, cerebral, and cerebellar atrophy were not syndrome specific and were similar in control and patient groups. Global and regional brain atrophy was determined primarily by age. A prior neurologic insult was associated with reduced hippocampal and cerebellar volumes and an increased rate of cerebellar atrophy. Significant atrophy of the hippocampus, neocortex, or cerebellum occurred in 17% of patients compared with 6.7% of control subjects. Patients with and without significant volume reduction were comparable in terms of seizure frequency, antiepileptic drug (AED) use, and epilepsy duration, with no identifiable risk factors for the development of atrophy.


CONCLUSIONS
Overt structural cerebral damage is not an inevitable consequence of epileptic seizures. In general, brain volume reduction in epilepsy is the cumulative effect of an initial precipitating injury and age-related cerebral atrophy. Significant atrophy developed in individual patients, particularly those with temporal lobe and generalized epilepsy. Longer periods of observation may detect more subtle effects of seizures.
Liu
Rebecca S N
RS
The Department of Clinical and Experimental Epilepsy, Institute of Neurology, University College London, London, England.
Lemieux
Louis
L
Bell
Gail S
GS
Sisodiya
Sanjay M
SM
Bartlett
Philippa A
PA
Shorvon
Simon D
SD
Sander
Josemir W A S
JW
Duncan
John S
JS
D000293:Adolescent; D000328:Adult; D000368:Aged; D001921:Brain / Q000473:pathology*; D001931:Brain Mapping / Q000379:methods; D002531:Cerebellum / Q000473:pathology; D003430:Cross-Sectional Studies; D003625:Data Collection; D018450:Disease Progression; D004827:Epilepsy / Q000473:pathology*; D004833:Epilepsy, Temporal Lobe / Q000473:pathology; D005260:Female; D005500:Follow-Up Studies; D006624:Hippocampus / Q000473:pathology; D006801:Humans; D008137:Longitudinal Studies; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D019579:Neocortex / Q000473:pathology; D012307:Risk Factors