title: Automatic generation of absolute myocardial blood flow images using [15O]H2O and a clinical PET/CT scanner.
abstract: OBJECTIVE
  Parametric imaging of absolute myocardial blood flow (MBF) using [(15)O]H(2)O enables determination of MBF with high spatial resolution. The aim of this study was to develop a method for generating reproducible, high-quality and quantitative parametric MBF images with minimal user intervention.
  
  
  METHODS
  Nineteen patients referred for evaluation of MBF underwent rest and adenosine stress [(15)O]H(2)O positron emission tomography (PET) scans. Ascending aorta and right ventricular (RV) cavity volumes of interest (VOIs) were used as input functions. Implementation of a basis function method (BFM) of the single-tissue model with an additional correction for RV spillover was used to generate parametric images. The average segmental MBF derived from parametric images was compared with MBF obtained using nonlinear least-squares regression (NLR) of VOI data. Four segmentation algorithms were evaluated for automatic extraction of input functions. Segmental MBF obtained using these input functions was compared with MBF obtained using manually defined input functions.
  
  
  RESULTS
  The average parametric MBF showed a high agreement with NLR-derived MBF [intraclass correlation coefficient (ICC) = 0.984]. For each segmentation algorithm there was at least one implementation that yielded high agreement (ICC > 0.9) with manually obtained input functions, although MBF calculated using each algorithm was at least 10% higher. Cluster analysis with six clusters yielded the highest agreement (ICC = 0.977), together with good segmentation reproducibility (coefficient of variation of MBF <5%).
  
  
  CONCLUSIONS
  Parametric MBF images of diagnostic quality can be generated automatically using cluster analysis and a implementation of a BFM of the single-tissue model with additional RV spillover correction.
authors.affiliation: Department of Nuclear Medicine & PET Research, VU University Medical Center, PO Box 7057, 1007 MB Amsterdam, The Netherlands. h.harms@vumc.nl
authors.forename: Hendrik J
authors.initials: HJ
authors.lastname: Harms
authors.forename: Paul
authors.initials: P
authors.lastname: Knaapen
authors.forename: Stefan
authors.initials: S
authors.lastname: de Haan
authors.forename: Rick
authors.initials: R
authors.lastname: Halbmeijer
authors.forename: Adriaan A
authors.initials: AA
authors.lastname: Lammertsma
authors.forename: Mark
authors.initials: M
authors.lastname: Lubberink
mesh_terms: D000328:Adult; D000368:Aged; D000465:Algorithms; D001331:Automation; D005260:Female; D006352:Heart Ventricles / Q000000981:diagnostic imaging; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000379:methods*; D021621:Imaging, Three-Dimensional; D008297:Male; D008875:Middle Aged; D055414:Myocardial Perfusion Imaging / Q000379:methods*; D010104:Oxygen Radioisotopes; D049268:Positron-Emission Tomography / Q000379:methods*; D015203:Reproducibility of Results; D012189:Retrospective Studies; D013997:Time Factors; D014057:Tomography, X-Ray Computed / Q000379:methods*; D014867:Water
chemical_list: D010104:Oxygen Radioisotopes; D014867:Water