T. Salmenpera et al., Hippocampal and amygdaloid damage in partial epilepsy - A cross-sectional MRI study of 241 patients, EPILEPSY R, 46(1), 2001, pp. 69-82
Patients with drug-refractory temporal lobe epilepsy (TLE) often have hippo
campal and amygdaloid damage. The present study investigated the factors as
sociated with the occurrence and severity of damage in patients with partia
l epilepsy. Magnetic resonance imaging was used to measure the volumes of t
he hippocampus and the amygdala in 241 patients with different durations of
epilepsy. We also investigated the association of damage with the location
of seizure focus and clinical factors (age at onset of seizures, lifetime
seizure number and medical history of complex febrile convulsions, intracra
nial infection or status epilepticus) with regression analysis. We found th
at high lifetime seizure number (P < 0.05), history of complex febrile conv
ulsions (P < 0.01), and age 15 years at the time of the first seizure (P <
0.01) were significant risk factors far reduced hippocampal volume in TLE p
atients. The severity of amygdaloid damage did not differ between TLE patie
nts with different durations of epilepsy or seizure frequency, but complex
febrile convulsions (P < 0.05) and intracranial infection (P < 0.05) were a
ssociated with amygdaloid damage. In patients with extratemporal or unclass
ified partial epilepsy, the hippocampal and amygdaloid volumes did not diff
er when patients with different durations of epilepsy were compared with co
ntrols. The present findings indicate that a high seizure number, the occur
rence of complex febrile convulsions, and an early onset of seizures contri
bute to hippocampal volume reduction in patients with TLE. The data provide
d have important implications with regard to early and effective management
and seizure control in vulnerable patients. (C) 2001 Published by Elsevier
Science B.V.