title: Reduced GABAA receptor density contralateral to a potentially epileptogenic MRI abnormality in a patient with complex partial seizures.
abstract: Imaging cerebral GABAA receptor density (GRD) with single-photon emission tomography (SPET) and iodine-123 iomazenil is highly accurate in lateralizing epileptogenic foci in patients with complex partial seizures of temporal origin. Limited knowledge exists on how iomazenil SPET compares with magnetic resonance imaging (MRI) in this regard. We present a patient with complex partial seizures in whom MRI had identified an arachnoid cyst anterior to the tip of the left temporal lobe. Contralaterally to this structural abnormality, interictal electroencephalography (EEG) performed after sleep deprivation disclosed an intermittent frontotemporal dysrhythmic focus with slow and sharp waves. On iomazenil SPET images GRD was significantly reduced in the right temporal lobe and thus contralaterally to the MRI abnormality, but ipsilaterally to the pathological EEG findings. These data suggest that iomazenil SPET may significantly contribute to the presurgical evaluation of epileptic patients even when MRI identifies potentially epileptogenic structural lesions.
authors.affiliation: Department of Nuclear Medicine, Westfälische Wilhelms-Universität Münster, Albert-Schweitzer-Strasse 33, D-48129 Münster, Germany.
authors.forename: T
authors.initials: T
authors.lastname: Kuwert
authors.forename: S R
authors.initials: SR
authors.lastname: Stodieck
authors.forename: C
authors.initials: C
authors.lastname: Puskás
authors.forename: B
authors.initials: B
authors.lastname: Diehl
authors.forename: Z
authors.initials: Z
authors.lastname: Puskaś
authors.forename: G
authors.initials: G
authors.lastname: Schuierer
authors.forename: B
authors.initials: B
authors.lastname: Vollet
authors.forename: O
authors.initials: O
authors.lastname: Schober
mesh_terms: D000328:Adult; D016080:Arachnoid Cysts / Q000175:diagnosis*; D004569:Electroencephalography; D017029:Epilepsy, Complex Partial / Q000175:diagnosis* / Q000000981:diagnostic imaging*; D005260:Female; D005442:Flumazenil / Q000031:analogs & derivatives*; D006801:Humans; D007457:Iodine Radioisotopes; D008279:Magnetic Resonance Imaging; D011963:Receptors, GABA-A / Q000032:analysis*; D013702:Temporal Lobe / Q000000981:diagnostic imaging* / Q000473:pathology; D015899:Tomography, Emission-Computed, Single-Photon
chemical_list: D007457:Iodine Radioisotopes; D011963:Receptors, GABA-A; D005442:Flumazenil; C063038:iomazenil