Article

[11C]flumazenil positron emission tomography visualizes frontal epileptogenic regions.

Department of Neuroscience, Karolinska Institute, Stockholm, Sweden.
Epilepsia (impact factor: 3.96). 01/1996; 36(12):1225-32. pp.1225-32
Source: PubMed

ABSTRACT Presently available noninvasive methods correctly localize epileptogenic regions in only approximately 50% of patients with frontal lobe epilepsy (FLE). Earlier studies have shown that temporal lobe epileptogenic regions may be identified readily by positron emission tomography (PET) measurements of regional benzodiazepine (BZD) receptor binding. We tested the specific applicability of this method in patients with FLE. Six patients with frontal partial seizures and 7 healthy men were investigated with PET and the BZD receptor ligand [11C]flumazenil. All patients had magnetic resonance (MR) brain scans. The independent assessment of seizure-onset region was based on seizure semiology, intra- and extracranial EEG and, in 4 cases, also on [18F]fluorodeoxyglucose (FDG)-PET. The epileptic focus/seizure-generating region was correctly identified by [11C]flumazenil PET in all patients. This region was characterized by a significant reduction in BZD receptor density. The area with reduced BZD receptor density was better delimited than the corresponding hypometabolic region, which was observed in 50% of patients investigated with [18F]FDG-PET. MRI was normal in 5 patients. Visualization of BZD receptors with [11C]flumazenil PET appears to be a promising approach for noninvasive identification of frontal lobe epileptogenic regions.

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Keywords

4 cases
 
5 patients
 
7 healthy men
 
[11C]flumazenil PET
 
BZD receptor density
 
BZD receptor ligand [11C]flumazenil
 
BZD receptors
 
corresponding hypometabolic region
 
epileptic focus/seizure-generating region
 
extracranial EEG
 
frontal lobe epilepsy
 
frontal lobe epileptogenic regions
 
frontal partial seizures
 
independent assessment
 
positron emission tomography
 
promising approach
 
regional benzodiazepine
 
seizure semiology
 
specific applicability
 
temporal lobe epileptogenic regions