title: Influence of the choice of software package on the outcome of semiquantitative MR myocardial perfusion analysis.
abstract: OBJECTIVE
  To assess the repeatability and reproducibility of semiquantitative magnetic resonance (MR) perfusion analysis performed by using different software packages.
  
  
  METHODS
  The study protocol was approved by the institutional ethics committee. Informed consent was obtained from each patient. Semiquantitative perfusion analysis was performed twice by two independent observers using four dedicated software packages. MR perfusion datasets originated from eight patients with known single-vessel disease who were scheduled for percutaneous coronary intervention (PCI) on the basis of coronary angiography findings. Each patient underwent two examinations: 1 day before and 1 day after PCI. Repeatability (intra- and interobserver agreements) and reproducibility (intersoftware agreement) were evaluated for perfusion upslope and myocardial perfusion reserve index with Student t test and Bland-Altman analyses.
  
  
  RESULTS
  Intra- and interobserver agreements were good and comparable for repeated measurements within each individual software platform (mean differences < 6%, intraclass correlation coefficient [ICC] ≥ 0.68). However, the intersoftware variability was significant (limits of agreement ≥ 65%, ICC ≤ 0.67) such that the values produced with the different software packages are not interchangeable.
  
  
  CONCLUSIONS
  The results indicate high repeatability within individual software but low reproducibility between different software packages, suggesting that within-group and/or sequential observation of semiquantitative perfusion parameters must be performed with the same software platform. Before semiquantitative perfusion analysis can be incorporated reliably into clinical studies, it is important to resolve the differences between the software packages.
authors.affiliation: Center for Medical Imaging North East Netherlands, University of Groningen, and Department of Radiology, University Medical Center, Hanzeplein 1, Groningen 9713 GZ, The Netherlands. a.handayani@umcg.nl
authors.forename: Astri
authors.initials: A
authors.lastname: Handayani
authors.forename: Paul E
authors.initials: PE
authors.lastname: Sijens
authors.forename: Daniel D
authors.initials: DD
authors.lastname: Lubbers
authors.forename: Pandji
authors.initials: P
authors.lastname: Triadyaksa
authors.forename: Matthys
authors.initials: M
authors.lastname: Oudkerk
authors.forename: Peter M A
authors.initials: PM
authors.lastname: van Ooijen
mesh_terms: D000368:Aged; D000465:Algorithms; D003324:Coronary Artery Disease / Q000000981:diagnostic imaging*; D005260:Female; D006801:Humans; D007089:Image Enhancement / Q000379:methods; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D018810:Magnetic Resonance Angiography / Q000379:methods*; D008297:Male; D008875:Middle Aged; D055414:Myocardial Perfusion Imaging / Q000379:methods*; D010363:Pattern Recognition, Automated / Q000379:methods*; D011859:Radiography; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D012984:Software; D012986:Software Validation