title: Kinetic analysis of [11C]befloxatone in the human brain, a selective radioligand to image monoamine oxidase A.
abstract: BACKGROUND
  [11C]Befloxatone measures the density of the enzyme monoamine oxidase A (MAO-A) in the brain. MAO-A is responsible for the degradation of different neurotransmitters and is implicated in several neurologic and psychiatric illnesses. This study sought to estimate the distribution volume (VT) values of [11C]befloxatone in humans using an arterial input function.
  
  
  METHODS
  Seven healthy volunteers were imaged with positron emission tomography (PET) after [11C]befloxatone injection. Kinetic analysis was performed using an arterial input function in association with compartmental modeling and with the Logan plot, multilinear analysis (MA1), and standard spectral analysis (SA) at both the regional and voxel level. Arterialized venous samples were drawn as an alternative and less invasive input function.
  
  
  RESULTS
  An unconstrained two-compartment model reliably quantified VT values in large brain regions. A constrained model did not significantly improve VT identifiability. Similar VT results were obtained using SA; however, the Logan plot and MA1 slightly underestimated VT values (about -10%). At the voxel level, SA showed a very small bias (+2%) compared to compartmental modeling, Logan severely underestimated VT values, and voxel-wise images obtained with MA1 were too noisy to be reliably quantified. Arterialized venous blood samples did not provide a satisfactory alternative input function as the Logan-VT regional values were not comparable to those obtained with arterial sampling in all subjects.
  
  
  CONCLUSIONS
  Binding of [11C]befloxatone to MAO-A can be quantified using an arterial input function and a two-compartment model or, in parametric images, with SA.
authors.affiliation: University of Bordeaux, CNRS, INCIA, UMR 5287, Talence 33400, France. paolo.zanotti-fregonara@chu-bordeaux.fr.
authors.forename: Paolo
authors.initials: P
authors.lastname: Zanotti-Fregonara
authors.forename: Claire
authors.initials: C
authors.lastname: Leroy
authors.forename: Dimitri
authors.initials: D
authors.lastname: Roumenov
authors.forename: Christian
authors.initials: C
authors.lastname: Trichard
authors.forename: Jean-Luc
authors.initials: JL
authors.lastname: Martinot
authors.forename: Michel
authors.initials: M
authors.lastname: Bottlaender