title: [Phase 2 clinical study of 123I-iomazenil in various cerebral diseases: part 1--examination of injection dose and clinical indications].
abstract: A phase 2 study of 123I-Iomazenil (IMZ) was performed to evaluate its clinical usefulness in SPECT imaging of central-type benzodiazepine receptors (BZR). A total of 246 patients with various central nervous system disorders [82 with epilepsy, 94 with cerebrovascular disease (CVD), 47 with degenerative disorders, 14 with mental disorders relating to BZR and 9 with other diseases] were intravenously injected with 111-222 MBq of IMZ. Early and late images were obtained 15 min and 180 min after injection as the mid-scan time, respectively. In comparison with regional cerebral blood flow (rCBF) images, the uptake of IMZ in the late images, which reflect the regional distribution of BZR, was relatively preserved compared to the uptake of CBF tracers in most of the patients with CVD. In the area of hyperperfusion in the subacute phase of cerebral infarction, however, the defects of IMZ uptake were accompanied by increased uptake of the CBF tracers. On the other hand, late IMZ uptake in most of the patients with the other diseases was decreased more significantly than the uptake of the CBF tracers, suggesting that cortical neuronal damage is more prominent than rCBF in these diseases compared to the vascular perfusional state. No adverse reactions were recognized relating to the IMZ administration. These results suggest that IMZ may provide us with valuable information for assessing pathophysiological state in the brain, which are difficult to achieve with other imaging modalities.
authors.affiliation: Fukui Medical School, Japan.
authors.forename: K
authors.initials: K
authors.lastname: Torizuka
authors.forename: K
authors.initials: K
authors.lastname: Uemura
authors.forename: M
authors.initials: M
authors.lastname: Tohru
authors.forename: Y
authors.initials: Y
authors.lastname: Yonekura
authors.forename: J
authors.initials: J
authors.lastname: Nakagawara
authors.forename: H
authors.initials: H
authors.lastname: Fukuyama
authors.forename: K
authors.initials: K
authors.lastname: Matsuda
authors.forename: K
authors.initials: K
authors.lastname: Morimoto
mesh_terms: D000328:Adult; D001927:Brain Diseases / Q000000981:diagnostic imaging*; D005260:Female; D005442:Flumazenil / Q000008:administration & dosage / Q000031:analogs & derivatives*; D006801:Humans; D007457:Iodine Radioisotopes / Q000008:administration & dosage; D008297:Male; D001523:Mental Disorders / Q000000981:diagnostic imaging; D008875:Middle Aged; D011963:Receptors, GABA-A / Q000378:metabolism; D015899:Tomography, Emission-Computed, Single-Photon
chemical_list: D007457:Iodine Radioisotopes; D011963:Receptors, GABA-A; D005442:Flumazenil; C063038:iomazenil