title: Presurgical multimodality neuroimaging in electroencephalographic lateralized temporal lobe epilepsy.
abstract: The purpose of this study was to compare 2-[18F]fluoro-2-deoxy-D-glucose positron emission tomography (FDG-PET), hippocampal volumetry (HV), T2 relaxometry, and proton magnetic resonance spectroscopic imaging (1H-MRSI) in the presurgical neuroimaging lateralization of patients with nonlesional, electroencephalogram (EEG)-defined unilateral temporal lobe epilepsy (TLE). Twenty-five patients were prospectively studied, along with age-matched controls. T2 relaxometry examinations were performed in 13 patients. Comparison of FDG-PET, HV, and 1H-MRSI was possible in 23 patients. FDG-PET lateralized 87% of patients, HV 65%, N-acetyl aspartate (NAA)/(choline [Cho] + creatine [Cr]) 61%, and [NAA] 57%. Combined HV and NAA/(Cho + Cr) results lateralized 83% of the patients, a value similar to PET. Of 10 patients with normal magnetic resonance imaging (MRI) scans, 2 were lateralized with HV, 6 with FDG-PET, 4 with NAA/(Cho + Cr), and 3 with [NAA]. T2 relaxometry lateralized no patients without hippocampal atrophy. Bilateral abnormality was present in 29 to 33% of patients with 1H-MRSI measures and 17% with HV. Only hippocampal atrophy correlated with postoperative seizure-free outcome. FDG-PET remains the most sensitive imaging method to correlate with EEG-lateralized TLE. Both FDG-PET and 1H-MRSI can lateralize patients with normal MRI, but only the presence of relative unilateral hippocampal atrophy is predictive of seizure-free outcome. Bilaterally abnormal MRI and 1H-MRSI measures do not preclude good surgical outcome.
authors.affiliation: Department of Neurology, University of California, San Francisco, School of Medicine, USA.
authors.forename: R C
authors.initials: RC
authors.lastname: Knowlton
authors.forename: K D
authors.initials: KD
authors.lastname: Laxer
authors.forename: G
authors.initials: G
authors.lastname: Ende
authors.forename: R A
authors.initials: RA
authors.lastname: Hawkins
authors.forename: S T
authors.initials: ST
authors.lastname: Wong
authors.forename: G B
authors.initials: GB
authors.lastname: Matson
authors.forename: H A
authors.initials: HA
authors.lastname: Rowley
authors.forename: G
authors.initials: G
authors.lastname: Fein
authors.forename: M W
authors.initials: MW
authors.lastname: Weiner
mesh_terms: D000328:Adult; D016022:Case-Control Studies; D004569:Electroencephalography; D004833:Epilepsy, Temporal Lobe / Q000000981:diagnostic imaging* / Q000473:pathology* / Q000503:physiopathology / Q000601:surgery; D005260:Female; D019788:Fluorodeoxyglucose F18; D007839:Functional Laterality; D006624:Hippocampus / Q000000981:diagnostic imaging / Q000473:pathology; D006801:Humans; D008279:Magnetic Resonance Imaging; D009682:Magnetic Resonance Spectroscopy; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D011446:Prospective Studies; D019275:Radiopharmaceuticals; D014055:Tomography, Emission-Computed / Q000379:methods; D016896:Treatment Outcome
chemical_list: D019275:Radiopharmaceuticals; D019788:Fluorodeoxyglucose F18