title: Validation of reference tissue modelling for [11C]flumazenil positron emission tomography following head injury.
abstract: OBJECTIVE
  [(11)C]Flumazenil ([(11)C]FMZ) positron emission tomography (PET) can be used as a measure of neuronal loss. The purpose of this study was to validate reference tissue kinetic modelling of [(11)C]FMZ PET within a group of patients with head injury.
  
  
  METHODS
  Following earlier studies, the pons was used as the reference region. PET scans were performed on 16 controls and 11 patients at least 6 months following injury, each of whom also had arterial blood sampling to provide whole blood and metabolite-corrected plasma input functions. Regional non-displaceable binding potentials (BP(ND)) were calculated from five reference tissue models and compared to BP(ND) from arterial input models. For the patients, the regions included a peri-lesional region of interest (ROI).
  
  
  RESULTS
  Total distribution volume of the pons was not significantly different between control and patient groups (P = 0.24). BP(ND) from all the reference tissue approaches correlated well with BP(ND) from the plasma input models for both controls (r (2) = 0.98-1.00; P < 0.001) and patients (r (2) = 0.99-1.00; P < 0.001). For the peri-lesional regions (n = 11 ROI values), the correlation was also high (r (2) = 0.91).
  
  
  CONCLUSIONS
  These results indicate that reference tissue modelling with the pons as the reference region is valid for [(11)C]FMZ PET in head-injured patients at 6 months following injury within both normal appearing and peri-lesional brain regions.
authors: University Division of Anaesthesia, University of Cambridge, Cambridge, UK.
authors: Thomas
authors: T
authors: Geeraerts
authors: Jonathan P
authors: JP
authors: Coles
authors: Franklin I
authors: FI
authors: Aigbirhio
authors: John D
authors: JD
authors: Pickard
authors: David K
authors: DK
authors: Menon
authors: Tim D
authors: TD
authors: Fryer
authors: Young T
authors: YT
authors: Hong
mesh_terms: D000328:Adult; D000368:Aged; D001158:Arteries / Q000000981:diagnostic imaging / Q000503:physiopathology; D002250:Carbon Radioisotopes; D006259:Craniocerebral Trauma / Q000000981:diagnostic imaging* / Q000378:metabolism / Q000473:pathology* / Q000503:physiopathology; D005260:Female; D005442:Flumazenil; D006801:Humans; D007700:Kinetics; D008297:Male; D008875:Middle Aged; D008954:Models, Biological; D011149:Pons / Q000000981:diagnostic imaging / Q000378:metabolism; D049268:Positron-Emission Tomography / Q000592:standards*; D012015:Reference Standards; D055815:Young Adult
chemical_list: D002250:Carbon Radioisotopes; D005442:Flumazenil