title: Impact of a motion correction algorithm on image quality in patients undergoing CT angiography: A randomized controlled trial.
abstract: OBJECTIVE
  To investigate the motion correction algorithm Snapshot-Freeze (SSF) compared to standard reconstruction (STD) in patients randomized to receive beta-blockers (BB) or no beta-blockers (non-BB) before coronary CT, and to investigate if SSF can replace BB.
  
  
  METHODS
  One hundred and forty patients scheduled for coronary CT were randomized. All images were reconstructed by the SSF and STD algorithms. Image quality was evaluated according to Likert score (1: excellent, 2: good, 3: adequate, 4: non-diagnostic) and presence of artifacts was noted.
  
  
  RESULTS
  Images from 64 patients in the BB group (mean HR 56±4bpm) and 51 patients in the non-BB group (mean HR 67±7bpm) were analyzed. Twenty five patients were excluded because of tachycardia, bradycardia or reconstruction errors in SSF. SSF increased the number of excellent images in both groups compared to the STD algorithm (BB: 59% vs.44%; non-BB: 25% vs. 8%), but the number of non-diagnostic images was not significantly reduced. SSF reduced motion artifacts (BB: 11% vs. 31%; non-BB: 49% vs. 75%), but despite this reduction, motion artifacts in non-BB were still more frequent compared to the BB group analyzed by STD (49% vs. 31%).
  
  
  CONCLUSIONS
  SSF improves image quality and reduces motion artifacts, but does not compensate for the absence of BB.
authors.affiliation: Department of Medical Research, OUH Svendborg Hospital, Institute of Regional Health Research, Valdemarsgade 53, 5700 Svendborg, Denmark. Electronic address: Hussam.sheta@rsyd.dk.
authors.forename: Hussam M
authors.initials: HM
authors.lastname: Sheta
authors.affiliation: Department of Medical Research, OUH Svendborg Hospital, Institute of Regional Health Research, Valdemarsgade 53, 5700 Svendborg, Denmark.
authors.forename: Kenneth
authors.initials: K
authors.lastname: Egstrup
authors.affiliation: Department of Medical Research, OUH Svendborg Hospital, Institute of Regional Health Research, Valdemarsgade 53, 5700 Svendborg, Denmark.
authors.forename: Mirza
authors.initials: M
authors.lastname: Husic
authors.affiliation: Department of Medical Research, OUH Svendborg Hospital, Institute of Regional Health Research, Valdemarsgade 53, 5700 Svendborg, Denmark.
authors.forename: Laurits J
authors.initials: LJ
authors.lastname: Heinsen
authors.affiliation: Erasmus University Medical Centre Rotterdam, 's-Gravendijkwal 230, 3015 CE Rotterdam, Netherlands.
authors.forename: Koen
authors.initials: K
authors.lastname: Nieman
authors.affiliation: Institute of Regional Health Research, OUH Svendborg Sygehus, Valdemarsgade 53, 5700 Svendborg, Denmark.
authors.forename: Jess
authors.initials: J
authors.lastname: Lambrechtsen
mesh_terms: D000368:Aged; D000465:Algorithms; D016477:Artifacts; D000072226:Computed Tomography Angiography / Q000379:methods*; D017023:Coronary Angiography / Q000379:methods*; D003324:Coronary Artery Disease / Q000000981:diagnostic imaging*; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000379:methods*; D008297:Male; D008875:Middle Aged; D009038:Motion
keywords: Coronary CT; Heart rate lowering medication; Image quality; Motion artifacts; Motion correction algorithm; Snapshot Freeze