title: Computer-assisted calculation of myocardial infarct size shortens the evaluation time of contrast-enhanced cardiac MRI.
abstract: BACKGROUND
  Delayed enhancement magnetic resonance imaging depicts scar in the left ventricle which can be quantitatively measured. Manual segmentation and scar determination is time consuming. The purpose of this study was to evaluate a software for infarct quantification, to compare with manual scar determination, and to measure the time saved.
  
  
  METHODS
  Delayed enhancement magnetic resonance imaging was performed in 40 patients where myocardial perfusion single photon emission computed tomography imaging showed irreversible uptake reduction suggesting a myocardial scar. After segmentation, the semi-automatic software was applied. A scar area was displayed, which could be corrected and compared with manual delineation. The different time steps were recorded with both methods.
  
  
  RESULTS
  The software shortened the average evaluation time by 12.4 min per cardiac exam, compared with manual delineation. There was good correlation of myocardial volume, infarct volume and infarct percentage (%) between the two methods, r = 0.95, r = 0.92 and r = 0.91 respectively.
  
  
  CONCLUSIONS
  A computer software for myocardial volume and infarct size determination cut the evaluation time by more than 50% compared with manual assessment, with maintained clinical accuracy.
authors.affiliation: Department of Clinical Physiology, County Hospital Ryhov, Jönköping, and Center for Medical Image Science and Visualization, CMIV, Linköping, Sweden. lene.rosendahl@lj.se
authors.forename: Lene
authors.initials: L
authors.lastname: Rosendahl
authors.forename: Peter
authors.initials: P
authors.lastname: Blomstrand
authors.forename: Einar
authors.initials: E
authors.lastname: Heiberg
authors.forename: Jan
authors.initials: J
authors.lastname: Ohlsson
authors.forename: Per-Gunnar
authors.initials: PG
authors.lastname: Björklund
authors.forename: Britt-Marie
authors.initials: BM
authors.lastname: Ahlander
authors.forename: Jan
authors.initials: J
authors.lastname: Engvall
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000465:Algorithms; D003287:Contrast Media; D005260:Female; D019786:Gadolinium DTPA; D006801:Humans; D007090:Image Interpretation, Computer-Assisted; D019028:Magnetic Resonance Imaging, Cine; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000000981:diagnostic imaging / Q000473:pathology*; D015588:Observer Variation; D011237:Predictive Value of Tests; D011379:Prognosis; D015203:Reproducibility of Results; D012984:Software; D013997:Time Factors; D015899:Tomography, Emission-Computed, Single-Photon
chemical_list: D003287:Contrast Media; D019786:Gadolinium DTPA