title: PET molecular imaging to investigate higher brain dysfunction in patients with neurotrauma.
abstract: BACKGROUND
  Many neurotrauma patients suffer from higher brain dysfunction even when focal brain damage is not detected with MRI. We performed functional imaging with positron emission tomography (PET) to clarify the relationship between the functional deficit and symptoms of such patients.
  
  
  METHODS
  Patients who complain of higher brain dysfunction without apparent morphological cortical damage were recruited. Thirteen patients underwent PET study to image glucose metabolism by (18)F-FDG, and central benzodiazepine receptor (cBZD-R) by (11)C-flumazenil, together with measurement of cognition.
  
  
  RESULTS
  Diffuse axonal injury (DAI) patients have a significant decrease in glucose metabolism and cBZD-R distribution in the cingulated cortex than normal controls. Score of cognition test was variable among patients. The degree of decreased glucose metabolism and cBZD-R in the dominant hemisphere corresponded well to the severity of cognitive disturbance. Patients with a milder type of diffuse brain injury (i.e., cerebral concussion) also showed abnormal glucose metabolism and cBZD-R distribution when they suffered from cognitive deficit.
  
  
  CONCLUSIONS
  PET molecular imaging was useful for depicting the cortical dysfunction of neurotrauma patients even when morphological change was not apparent. This method may be promising in clarifying the pathophysiology of higher brain dysfunction of patients with neurotrauma, but without morphological abnormality.
authors.affiliation: Department of Neurosurgery, Tokyo Medical and Dental University, Bunkyo-ku, Tokyo, Japan, nariai.nsrg@tmd.ac.jp
authors.forename: Tadashi
authors.initials: T
authors.lastname: Nariai
authors.forename: Motoki
authors.initials: M
authors.lastname: Inaji
authors.forename: Yoji
authors.initials: Y
authors.lastname: Tanaka
authors.forename: Mikio
authors.initials: M
authors.lastname: Hiura
authors.forename: Chihiro
authors.initials: C
authors.lastname: Hosoda
authors.forename: Kenji
authors.initials: K
authors.lastname: Ishii
authors.forename: Kikuo
authors.initials: K
authors.lastname: Ohno
mesh_terms: D000328:Adult; D001921:Brain / Q000000981:diagnostic imaging; D001931:Brain Mapping; D002247:Carbon Isotopes; D020833:Diffuse Axonal Injury / Q000000981:diagnostic imaging* / Q000473:pathology*; D005260:Female; D005442:Flumazenil; D019788:Fluorodeoxyglucose F18; D018757:GABA Modulators; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008279:Magnetic Resonance Imaging; D008297:Male; D009483:Neuropsychological Tests; D049268:Positron-Emission Tomography; D055815:Young Adult
chemical_list: D002247:Carbon Isotopes; D018757:GABA Modulators; D019788:Fluorodeoxyglucose F18; D005442:Flumazenil