Purpose
To evaluate (a) radiation dose for coronary calcium scoring (CCS) and coronary CT angiography (cCTA) and (b) dose-influencing parameters with a third-generation dual-source CT (3rd gen DSCT) in an unselected patient cohort.
Methods and Materials
In 159 consecutive patients,
a total of 137 CCSs and 147 cCTAs were performed for evaluation of coronary artery disease with a 3rd gen DSCT.
Anterior-posterior (AP) and lateral thoracic dimensions were measured from the CT data sets.
Sum of AP and lateral dimensions,
and effective diameters were calculated.
Effective radiation dose was estimated by multiplying the dose-length product with a conversion factor of 0.014 mSv/mGy*cm.
To account for differences in patient habitus,
size-specific dose estimates (SSDEs) were calculated from volume CT dose indices based...
Results
Mean age of patients was 57.6 years ± 12.3 (standard deviation).
Mean body mass index was 27.9 kg/m2 ± 6.3 (range,
17.4 - 50.4 kg/m2).
Prospectively ECG-gated high-pitch spiral (hereafter: high-pitch spiral) was used in 52 patients (35.4%),
prospectively ECG-gated sequential acquisition (hereafter: sequential acquisition) in 55 (37.4%),
and retrospectively ECG-gated spiral acquisition (hereafter: retrospective spiral) in 40 patients (27.2%).
Median effective radiation dose was 0.54 mSv (interquartile range [IQR] 0.42 - 0.64 mSv) for CCS,
0.80 mSv (IQR 0.60 - 0.98 mSv) for high-pitch...
Conclusion
Submillisievert radiation dose is feasible for CCS and high-pitch spiral in the vast majority of patients.
Compared to the latter,
sequential acquisition and retrospective spiral are associated with about 2- and 10-times higher SSDEs,
respectively.