Longitudinal quantitative hippocampal magnetic resonance imaging study of adults with newly diagnosed partial seizures: one-year follow-up results.
OBJECTIVE
We wished to establish whether hippocampal changes occur in 1 year in adults with newly diagnosed partial seizures and, if so, to identify possible causes and mechanisms.


METHODS
Thirty-six adult patients with newly diagnosed partial seizures underwent a magnetic resonance imaging (MRI) scan of the brain including hippocampal volume and T2 relaxation time (HCT2) measurement and had a follow-up quantitative MRI scan approximately 1 year after the baseline MRI scan.


RESULTS
At baseline, 4 patients (11%) had hippocampal sclerosis (HS), 4 (11%) had abnormalities other than HS, and 28 had a normal MRI scan (78%). Twenty-three patients (64%) had recurrent seizures in the period between the two MRI scans. One of the 4 patients with HS, who had daily seizures, had significantly increased HCT2 values on follow-up, possibly reflecting progressive hippocampal damage. None of the 32 patients with MRI findings other than HS at baseline progressed to HS on follow-up. However, 2 of the 32 patients had significant hippocampal changes, probably related to resolution of inflammatory swelling or edema after seizures were controlled.


CONCLUSIONS
Subtle changes in hippocampi can occur in 1 year in adults with newly diagnosed partial seizures, which could be due to resolution of edema after seizure control or to hippocampal changes associated with frequent and daily seizures. Follow-up of the studied cohort for several years will be required to settle the question of whether progressive hippocampal damage occurs in temporal lobe epilepsy (TLE).
Van Paesschen
W
W
Epilepsy Research Group, University Department of Clinical Neurology, National Hospital for Neurology and Neurosurgery, London, UK.
Duncan
J S
JS
Stevens
J M
JM
Connelly
A
A
D000293:Adolescent; D000328:Adult; D000927:Anticonvulsants / Q000627:therapeutic use; D001284:Atrophy / Q000473:pathology; D001929:Brain Edema / Q000473:pathology; D018450:Disease Progression; D004828:Epilepsies, Partial / Q000175:diagnosis* / Q000188:drug therapy / 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; D008297:Male; D008875:Middle Aged; D012598:Sclerosis / Q000473:pathology
D000927:Anticonvulsants