title: Compensation for spill-in and spill-out partial volume effects in cardiac PET imaging.
abstract: BACKGROUND
  Partial volume effects (PVEs) in PET imaging result in incorrect regional activity estimates due to both spill-out and spill-in from activity in neighboring regions. It is important to compensate for both effects to achieve accurate quantification. In this study, an image-based partial volume compensation (PVC) method was developed and validated for cardiac PET.
  
  
  RESULTS
  The method uses volume-of-interest (VOI) maps segmented from contrast-enhanced CTA images to compensate for both spill-in and spill-out in each VOI. The PVC method was validated with simulation studies and also applied to images of dog cardiac perfusion PET data. The PV effects resulting from cardiac motion and myocardial uptake defects were investigated and the efficacy of the proposed PVC method in compensating for these effects was evaluated.
  
  
  RESULTS
  Results indicate that the magnitude and the direction of PVEs in cardiac imaging change over time. This affects the accuracy of activity distributions estimates obtained during dynamic studies. The defect regions have different PVEs as compared to the normal myocardium. Cardiac motion contributes around 10% to the PVEs. PVC effectively removed both spill-in and spill-out in cardiac imaging.
  
  
  CONCLUSIONS
  PVC improved left ventricular wall uniformity and quantitative accuracy. The best strategy for PVC was to compensate for the PVEs in each cardiac phase independently and treat severe uptake defects as independent regions from the normal myocardium.
authors.affiliation: The Russell H. Morgan Department of Radiology and Radiological Sciences, School of Medicine, Johns Hopkins University, 601 N Caroline St, JHOC 4263, Baltimore, MD 21287, USA. duyong@jhu.edu
authors.forename: Yong
authors.initials: Y
authors.lastname: Du
authors.forename: Igal
authors.initials: I
authors.lastname: Madar
authors.forename: Martin J
authors.initials: MJ
authors.lastname: Stumpf
authors.forename: Xing
authors.initials: X
authors.lastname: Rong
authors.forename: George S K
authors.initials: GS
authors.lastname: Fung
authors.forename: Eric C
authors.initials: EC
authors.lastname: Frey
mesh_terms: D000465:Algorithms; D000818:Animals; D001921:Brain / Q000473:pathology; D003198:Computer Simulation; D004285:Dogs; D006321:Heart / Q000000981:diagnostic imaging*; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000379:methods; D009010:Monte Carlo Method; D009038:Motion; D009206:Myocardium / Q000473:pathology*; D019047:Phantoms, Imaging; D049268:Positron-Emission Tomography / Q000379:methods*; D015203:Reproducibility of Results; D013997:Time Factors; D016277:Ventricular Function, Left