title: (18)F-FDG PET in localization of frontal lobe epilepsy: comparison of visual and SPM analysis.
abstract: The sensitivity of (18)F-FDG PET to localize epileptogenic zones in frontal lobe epilepsy was evaluated by both visual assessment and statistical parametric mapping (SPM).
  
  
  METHODS
  Twenty-nine patients with frontal lobe epilepsy were examined. All patients showed good outcome after surgical resection (Engel class I or II). On pathologic examination, 22 patients had cortical dysplasia, 4 had tumors, 1 had cortical scars, and 2 had an old infarct. Hypometabolic lesions were found on (18)F-FDG PET images by both visual assessment and SPM analysis. On SPM analysis, the cutoff threshold was varied and sensitivity to find epileptogenic zones was compared.
  
  
  RESULTS
  MRI showed structural lesions in 15 patients and normal findings in 14. (18)F-FDG PET correctly localized the epileptogenic zones in 16 patients (55%) by visual assessment. The sensitivity of (18)F-FDG PET was 36% in patients without structural lesions on MRI and 73% in patients with structural lesions. On SPM analysis, using an uncorrected probability value of 0.005 as the threshold, the sensitivity of SPM analysis was 66%, which was not statistically different from the sensitivity of visual assessment. The sensitivity decreased according to the decrease in probability value.
  
  
  CONCLUSIONS
  (18)F-FDG PET was sensitive in localizing epileptogenic zones by revealing hypometabolic areas in nonlesional patients with frontal lobe epilepsy as well as in lesional patients. SPM analysis showed a comparable sensitivity to visual assessment and could be used as an aid in diagnosing epileptogenic zones in frontal lobe epilepsy.
authors.affiliation: Department of Nuclear Medicine, College of Medicine, Seoul National University, Seoul, Korea.
authors.forename: Yu Kyeong
authors.initials: YK
authors.lastname: Kim
authors.forename: Dong Soo
authors.initials: DS
authors.lastname: Lee
authors.forename: Sang Kun
authors.initials: SK
authors.lastname: Lee
authors.forename: Chun Kee
authors.initials: CK
authors.lastname: Chung
authors.forename: June-Key
authors.initials: JK
authors.lastname: Chung
authors.forename: Myung Chul
authors.initials: MC
authors.lastname: Lee
mesh_terms: D000328:Adult; D016022:Case-Control Studies; D017034:Epilepsy, Frontal Lobe / Q000000981:diagnostic imaging* / Q000601:surgery; D005260:Female; D019788:Fluorodeoxyglucose F18; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D015233:Models, Statistical; D019275:Radiopharmaceuticals; D012680:Sensitivity and Specificity; D014055:Tomography, Emission-Computed
chemical_list: D019275:Radiopharmaceuticals; D019788:Fluorodeoxyglucose F18