Reduction of benzodiazepine receptor binding is related to the seizure onset zone in extratemporal focal cortical dysplasia.
OBJECTIVE
Comparison of regional reduction of GABA receptor binding and seizure onset zone in patients with extratemporal epilepsy due to focal cortical dysplasia.


METHODS
Two patients with frontal lobe epilepsy who remained seizure free after partial frontal lobe resection were investigated with magnetic resonance imaging, positron emission tomography (PET) with 18F-fluoro-deoxy-glucose (FDG) and 11C-flumazenil, subdural EEG-video recordings, and postoperative benzodiazepine (BDZ)-receptor autoradiography.


RESULTS
The area of reduced BDZ-receptor binding as documented by preoperative flumazenil-PET and postoperative BDZ-receptor autoradiography corresponded to the seizure onset zone and was smaller than the interictal hypometabolism documented by FDG-PET.


CONCLUSIONS
Flumazenil-PET is a useful tool for localization of the epileptogenic zone in patients with extratemporal epilepsy caused by focal cortical dysplasia. Neuronal distribution of BDZ-receptor density confirms in vivo flumazenil-PET findings. The regional reduction of BDZ-receptor binding in focal cortical dysplasia seems to be confined to the seizure onset zone and not to the extent of dysplastic cortex.
Arnold
S
S
Department of Neurology, University of Munich, Germany.
Berthele
A
A
Drzezga
A
A
Tölle
T R
TR
Weis
S
S
Werhahn
K J
KJ
Henkel
A
A
Yousry
T A
TA
Winkler
P A
PA
Bartenstein
P
P
Noachtar
S
S
D000293:Adolescent; D000328:Adult; D001345:Autoradiography; D002250:Carbon Radioisotopes; D002540:Cerebral Cortex / Q000002:abnormalities* / Q000601:surgery; D004569:Electroencephalography / Q000706:statistics & numerical data; D017034:Epilepsy, Frontal Lobe / Q000175:diagnosis / Q000378:metabolism* / Q000601:surgery; D005442:Flumazenil; D019788:Fluorodeoxyglucose F18; D005625:Frontal Lobe / Q000378:metabolism / Q000601:surgery; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000706:statistics & numerical data; D008297:Male; D011963:Receptors, GABA-A / Q000378:metabolism*; D014055:Tomography, Emission-Computed / Q000706:statistics & numerical data
D002250:Carbon Radioisotopes; D011963:Receptors, GABA-A; D019788:Fluorodeoxyglucose F18; D005442:Flumazenil