Correlation of temporal lobe glucose metabolism with the Wada memory test.
OBJECTIVE
The goal of the present study was to examine the relationship of 18F-fluorodeoxyglucose positron emission tomography (FDG-PET) and the Wada memory test in lateralizing memory dominance and epileptic focus.


METHODS
FDG-PET and the Wada test were performed in 18 patients with temporal lobe epilepsy (TLE). The asymmetry indices of FDG-PET (PET-AI) were calculated in mesial, polar, anterolateral, midlateral, and posterolateral regions of the temporal lobe, and those of Wada memory test (Wada-AI) were obtained as well.


RESULTS
The Wada-AI was significantly correlated with PET-AI in mesial (r = 0.67, p = 0.003), polar (r = 0.55, p = 0.019), anterolateral (r = 0.55, p = 0.019), and midlateral (r = 0.51, p = 0.031) regions of the temporal lobe. However, after a linear regression analysis, PET-AI of only the mesial temporal region was significantly correlated with Wada-AI (p = 0.008). Wada-AI could correctly lateralize the seizure focus in 90% of the left TLE and 75% of the right TLE patients. The PET-AI of the mesial temporal region showed the highest sensitivity of seizure lateralization (80% of left TLE and 87.5% of right TLE). PET-AI of other temporal regions had lower sensitivities (50-80% of left TLE, 20-75% of right TLE). One or two patients showed false seizure lateralization by PET-AI on each temporal region.


CONCLUSIONS
Although FDG-PET hypometabolism is observed at both mesial and lateral regions of the temporal lobe in mesial TLE, mesial temporal region appeared to be a dominant and leading area for lateralizing Wada memory dominance and epileptic focus.
Hong
S B
SB
Epilepsy Program, Department of Neurology, Sungkyunkwan University School of Medicine, Seoul, Korea. sbhong@smc.samsung.co.kr
Roh
S Y
SY
Kim
S E
SE
Seo
D W
DW
D000293:Adolescent; D000328:Adult; D000654:Amobarbital / Q000494:pharmacology; D002648:Child; D004833:Epilepsy, Temporal Lobe / Q000175:diagnosis* / Q000000981:diagnostic imaging / Q000378:metabolism; D005260:Female; D019788:Fluorodeoxyglucose F18 / Q000378:metabolism; D007839:Functional Laterality / Q000187:drug effects / Q000502:physiology; D005947:Glucose / Q000378:metabolism*; D006801:Humans; D008297:Male; D008568:Memory / Q000187:drug effects* / Q000502:physiology; D008875:Middle Aged; D012680:Sensitivity and Specificity; D013702:Temporal Lobe / Q000000981:diagnostic imaging* / Q000378:metabolism*; D014055:Tomography, Emission-Computed / Q000706:statistics & numerical data*
D019788:Fluorodeoxyglucose F18; D000654:Amobarbital; D005947:Glucose