Reduction of benzodiazepine receptor binding is related to the seizure onset zone in extratemporal focal cortical dysplasia

Epilepsia. 2000 Jul;41(7):818-24. doi: 10.1111/j.1528-1157.2000.tb00248.x.


Purpose: 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.

Conclusion: 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.

Publication types

  • Case Reports

MeSH terms

  • Adolescent
  • Adult
  • Autoradiography
  • Carbon Radioisotopes
  • Cerebral Cortex / abnormalities*
  • Cerebral Cortex / surgery
  • Electroencephalography / statistics & numerical data
  • Epilepsy, Frontal Lobe / diagnosis
  • Epilepsy, Frontal Lobe / metabolism*
  • Epilepsy, Frontal Lobe / surgery
  • Flumazenil
  • Fluorodeoxyglucose F18
  • Frontal Lobe / metabolism
  • Frontal Lobe / surgery
  • Humans
  • Magnetic Resonance Imaging / statistics & numerical data
  • Male
  • Receptors, GABA-A / metabolism*
  • Tomography, Emission-Computed / statistics & numerical data


  • Carbon Radioisotopes
  • Receptors, GABA-A
  • Fluorodeoxyglucose F18
  • Flumazenil