LAUSR

AIMS 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%). CONCLUSION SSF improves image quality and reduces motion artifacts, but does not compensate for the absence of BB.