title: Automatic postprocessing for the assessment of quantitative human myocardial perfusion using MRI.
abstract: OBJECTIVE
  Quantitative determination of myocardial perfusion currently involves time-consuming postprocessing. This retrospective study presents automatic postprocessing consisting of image registration and image segmentation to obtain regional signal intensity time courses and quantitative perfusion values.
  
  
  METHODS
  The automatic postprocessing was tested in 75 examinations in volunteers and patients, 57 at rest and 18 under adenosine-induced stress, and compared with a manual evaluation. In a substudy consisting of 10 examinations, the interobserver variability of the manual evaluation was investigated.
  
  
  RESULTS
  Manual evaluation resulted in perfusion values with a median of 0.70 ml/g/min ranging from 0.03 to 3.68 ml/g/min. For all 75 examinations, the variability (standard deviation of the differences) between automatic and manual evaluation was 0.34 ml/g/min. Interobserver variability was of a similar order, 0.35 ml/g/min for all measurements.
  
  
  CONCLUSIONS
  Automatic evaluation was successfully applied to all datasets giving results equivalent to manual evaluation. The time of user interaction for one single slice could be reduced from 25 min for manual evaluation to less than 1 min using the automatic algorithm. This reduction may allow quantitative magnetic resonance perfusion imaging to become a routine clinical procedure.
authors.affiliation: Institute of Radiology, University of Würzburg, Oberdürrbacher Strasse 6, 97080 Würzburg, Germany. weng@roentgen.uni-wuerzburg.de
authors.forename: Andreas Max
authors.initials: AM
authors.lastname: Weng
authors.forename: Christian Oliver
authors.initials: CO
authors.lastname: Ritter
authors.forename: Joachim
authors.initials: J
authors.lastname: Lotz
authors.forename: Meinrad Joachim
authors.initials: MJ
authors.lastname: Beer
authors.forename: Dietbert
authors.initials: D
authors.lastname: Hahn
authors.forename: Herbert
authors.initials: H
authors.lastname: Köstler
mesh_terms: D000241:Adenosine; D000465:Algorithms; D003324:Coronary Artery Disease / Q000175:diagnosis*; D005260:Female; D006801:Humans; D007089:Image Enhancement / Q000379:methods; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D018810:Magnetic Resonance Angiography / Q000379:methods*; D008297:Male; D055414:Myocardial Perfusion Imaging / Q000379:methods*; D010363:Pattern Recognition, Automated / Q000379:methods*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity
chemical_list: D000241:Adenosine