Purpose
The aim of the study was to evaluate the potential reduction in radiation dose associated with advances in scanner technology in cardiovascular computed tomography (CT) angiography and to identify the unique predictors of potential dose saving among a substantial set of scan and patient parameters.
Methods and Materials
391 CT coronary angiograms (CTCA) performed in the clinical routine of our institution were randomly selected and retrospectively analyzed regarding the effective radiation dose (ED) applied to the patient.
ED [mSv] was estimated from the dose-length product [mGy×cm] and an organ weighting factor [k=0.014 mSv×(mGy×cm)−1].
100 examinations were performed on a 16-slice single-source multi-detector CT (SSCT; Somatom Sensation 16,
SiemensHealthcare,
Germany),
199 examinations on a first generation dual-source multi-detector CT (DSCT; Somatom Definition,
SiemensHealthcare,
Germany) and 92 examinations on a second generation DSCT (Somatom Definition...
Results
Mean ED for CTCA was 10.57±2.76 mSv on the SSCT scanner,
6.96±3.59 mSv on the DSCT standard scanner compared to 1.19±0.66 mSv on the Flash scanner (SSCT vs.
DSCT t-Test: p<0.001,
DSCT vs.
Flash t-Test p<0.001).
Compared to SSCT,
mean dose reduction with Flash was >88% (>82% compared to DSCT).
72% (66/92) of all examinations on the Flash scanner had an ED < 1 mSv.
Using mutivariate regression analysis the acquistion mode (Flash-Helix vs.
Gated-Helix; -6.48 mSv; p<0.001),
the body mass index (BMI; 0.24 mSv...
Conclusion
Latest dose-saving technology can yield drastic dose reductions in cardiovascular CT angiography shifting CTCA into the sub-mSv range while providing high diagnostic image quality.
References
Fink C,
Krissak R,
Henzler T,
et al.
Radiation dose at coronary CT angiography: second-generation dual-source CT versus single-source 64-MDCT and first-generation dual-source CT.
AJR Am J Roentgenol 2011;196:W550-W557.
Hausleiter J,
Meyer T,
Hermann F,
et al.
Estimated radiation dose associated with cardiac CT angiography.
JAMA 2009;301:500-507.