OBJECTIVES: A best-practice intervention previously demonstrated significant dose reduction over 1 year. We sought to evaluate if this reduction would be incremental and sustained by promoting new scanner technology in the context of an ongoing quality improvement program over a 3-year period in a statewide registry of coronary CT angiography (CTA).
METHODS: In this prospective, controlled, nonrandomized study involving 11,901 patients at 15 Michigan centers participating in the Advanced Cardiovascular Imaging Consortium (ACIC), radiation doses and image quality were compared between the following periods: control (May – June 2008)] vs. follow-up I (July 2008 – June 2009), and follow-up I vs. follow-up II (July 2009 – April 2011)]. Intervention during these study periods included continuous education, feedback and mandatory participation in this initiative.
RESULTS: The median radiation dose remained unchanged from control to follow-up I: dose-length product (DLP) of 697 (IQR 407, 1163) to 675 (IQR 418, 1146) mGy*cm (p=0.93). With the introduction of newer technology in follow-up I period, there was incremental 31% decrease during follow-up II to median DLP of 468 (IQR 292, 811) mGy*cm (P<0.0001). No significant change was noted in the percentage of diagnostic quality scans from follow-up I (92%) to follow-up II (92.7%).
CONCLUSIONS: Although ongoing application of a best-practice algorithm was associated with sustaining previously achieved targets, use of newer scanner technology resulted in incremental radiation dose reduction in a statewide coronary CTA registry without image quality degradation.