Temporal lobe epilepsy with amygdala enlargement: a morphologic and functional study.
OBJECTIVE
Temporal lobe epilepsy (TLE) with nontumoral amygdala enlargement (AE) has been reported to be a possible subtype of TLE without hippocampal sclerosis (HS). The purpose of this study was to clarify morphologic and functional characteristics of TLE with AE (TLE + AE).


METHODS
We evaluated gray matter volume and cerebral glucose hypometabolism using magnetic resonance imaging (MRI) voxel-based morphometry (VBM) and voxel-based statistical analysis of [(18) F]-fluorodeoxyglucose positron emission tomography (FDG-PET) images in 9 patients with TLE + AE as compared with controls. For VBM analysis, we recruited 30 age- and sex-matched healthy volunteers as controls. For the comparison of FDG-PET analysis, 9 patients with definite mesial TLE with HS (MTLE + HS), and 16 age- and sex-matched healthy controls were recruited.


RESULTS
In patients with TLE + AE, a significant increase in gray matter volume was found only in the affected amygdala, and no significant decrease in gray matter volume was detected. In addition, significant glucose hypometabolism was observed in the affected amygdala, whereas significant glucose hypometabolism in the hippocampus, a prominent feature of definite MTLE+HS, was not observed.


CONCLUSIONS
TLE + AE is different from MTLE + HS from morphologic and functional points of view, and the enlarged amygdala per se is potentially an epileptic focus in patients with partial epilepsy.
Radioisotope Research Center, Kyoto University, Kyoto, Japan; Human Brain Research Center, Kyoto University Graduate School of Medicine, Kyoto, Japan.
Shigetoshi
S
Takaya
Akio
A
Ikeda
Takahiro
T
Mitsueda-Ono
Riki
R
Matsumoto
Morito
M
Inouchi
Chihiro
C
Namiki
Naoya
N
Oishi
Nobuhiro
N
Mikuni
Koichi
K
Ishizu
Ryosuke
R
Takahashi
Hidenao
H
Fukuyama
D000328:Adult; D000368:Aged; D000679:Amygdala / Q000473:pathology* / Q000503:physiopathology*; D001931:Brain Mapping / Q000379:methods; D004833:Epilepsy, Temporal Lobe / Q000150:complications / Q000473:pathology* / Q000503:physiopathology*; D005260:Female; D005947:Glucose / Q000378:metabolism*; D066128:Gray Matter / Q000473:pathology* / Q000503:physiopathology*; D006801:Humans; D006984:Hypertrophy / Q000209:etiology / Q000473:pathology / Q000503:physiopathology; D008297:Male; D008875:Middle Aged; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D055815:Young Adult
D005947:Glucose