Clinical utility of 11C-flumazenil positron emission tomography in intractable temporal lobe epilepsy.
BACKGROUND
11C-flumazenil (FMZ) positron emission tomography (PET) is a new entrant into the armamentarium for pre-surgical evaluation of patients with intractable temporal lobe epilepsy (TLE).


OBJECTIVE
To analyze the clinical utility of FMZ PET to detect lesional and remote cortical areas of abnormal benzodiazepine receptor binding in relation to magnetic resonance imaging (MRI), 2-Deoxy-2 [18F] fluoro-D-glucose, (18F FDG) PET, electrophysiological findings and semiology of epilepsy in patients with intractable TLE.


METHODS
Patients underwent a high resolution MRI, prolonged Video-EEG monitoring before 18F FDG and 11C FMZ PET studies. Regional cortical FMZ PET abnormalities were defined on co-registered PET images using an objective method based on definition of areas of abnormal asymmetry (asymmetry index {AI}>10%).


METHODS
Prospective.


METHODS
Student's "t" test.


RESULTS
Twenty patients (Mean age: 35.2 years [20-51]; M:F=12:8) completed the study. Mean age at seizure onset was 10.3 years (birth-38 years); mean duration, 23.9 years (6-50 years). Concordance with the MRI lesion was seen in 10 patients (nine with hippocampal sclerosis and one with tuberous sclerosis). In the other 10, with either normal or ambiguous MRI findings, FMZ and FDG uptake were abnormal in all, concordant with the electrophysiological localization of the epileptic foci. Remote FMZ PET abnormalities (n=18) were associated with early age of seizure onset (P=0.005) and long duration of epilepsy (P=0.01).


CONCLUSIONS
FMZ-binding asymmetry is a sensitive method to detect regions of epileptic foci in patients with intractable TLE.
Padma
M V
MV
Department of Nuclear Medicine, Kettering Medical Center, Wright State University, Kettering, Ohio 45429, USA. vasanthapadma123@rediffmail.com
Simkins
Robert
R
White
Phillip
P
Satter
Martin
M
Christian
Brad T
BT
Dunigan
Kelly
K
Lee
Candi
C
Jacobs
M
M
Mukherjee
J
J
Mantil
Joseph C
JC
D000328:Adult; D004594:Electrophysiology; D004833:Epilepsy, Temporal Lobe / Q000000981:diagnostic imaging*; D005260:Female; D005442:Flumazenil; D019788:Fluorodeoxyglucose F18; D007839:Functional Laterality; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D049268:Positron-Emission Tomography; D019275:Radiopharmaceuticals
D019275:Radiopharmaceuticals; D019788:Fluorodeoxyglucose F18; D005442:Flumazenil