title: Cortical damage following traumatic brain injury evaluated by iomazenil SPECT and in vivo microdialysis.
abstract: [(123)I] iomazenil (IMZ) single photon emission computed tomography (SPECT) has been reported to be a useful marker of neuronal integrity. We evaluated cortical damage following traumatic brain injury (TBI) with IMZ SPECT at the acute stage. After conventional therapy for a cranial trauma, an IMZ SPECT re-evaluation was performed at the chronic stage. A reduction in IMZ uptake in the location of cerebral contusions was observed during the TBI acute phase; however, images of IMZ SPECT obtained during the chronic phase showed that areas with decreased IMZ distribution were remarkably reduced compared with those obtained during the acute phase. As a result of in vivo microdialysis study, the extracellular levels of glutamate in the cortex, where decreased IMZ distribution was shown during the acute phase, were increased during the 168-h monitoring period. During the chronic phase, IMZ uptake in the region with the microdialysis probes was recovered. The results suggest that this reduction in IMZ uptake might not be a sign of irreversible tissue damage in TBI.
authors.affiliation: Department of Neurosurgery, Yamaguchi University School of Medicine, Minami-Kogushi, Ube, Yamaguchi, Japan. hiroyasu@yamaguchi-u.ac.jp
authors.forename: Hiroyasu
authors.initials: H
authors.lastname: Koizumi
authors.forename: Hirosuke
authors.initials: H
authors.lastname: Fujisawa
authors.forename: Eiichi
authors.initials: E
authors.lastname: Suehiro
authors.forename: Hideyuki
authors.initials: H
authors.lastname: Iwanaga
authors.forename: Jyoji
authors.initials: J
authors.lastname: Nakagawara
authors.forename: Michiyasu
authors.initials: M
authors.lastname: Suzuki
mesh_terms: D001930:Brain Injuries / Q000000981:diagnostic imaging* / Q000473:pathology*; D002540:Cerebral Cortex / Q000000981:diagnostic imaging*; D005260:Female; D005442:Flumazenil / Q000031:analogs & derivatives; D006801:Humans; D008875:Middle Aged; D013997:Time Factors; D015899:Tomography, Emission-Computed, Single-Photon / Q000379:methods*; D014057:Tomography, X-Ray Computed
chemical_list: D005442:Flumazenil; C063038:iomazenil