Published online by Cambridge University Press: 15 November 2012
Multi-slice computed tomography (MSCT) has proven inseveral studies to have a high diagnostic accuracy for the detectionor exclusion of coronary artery disease. A major concern with coronaryMSCT, however, is the associated radiation exposure of patients.Recent studies suggest that use of a 64-slice scanner is associatedwith a non-negligible lifetime attributable risk of cancer. Severalstrategies can be used to reduce patient exposure in coronary MSCT.The purpose of this multicenter study was to investigate the effectsof the adjustment of tube voltage and current on radiation doseand image interpretability. MSCT with retrospective ECG gating was performedin 315 patients. The dose-length product (DLP) in the patients enrolledwith the dose reduction protocol resulted in a 36% overall reductionin the mean radiation dose (911 ± 289 mGy.cm) compared with thestandard protocol (1427 ± 226 mGy.cm, p < 0.001).Nevertheless, image interpretability was maintained. This studyon coronary MSCT demonstrates that the radiation dose can be significantly reducedby parameter optimization, with maintained image interpretability.