Diagnostic accuracy of low and high tube voltage coronary CT angiography using an X-ray tube potential-tailored contrast medium injection protocol
To compare the diagnostic accuracy between low-kilovolt peak (kVp) (≤ 100) and high-kVp (> 100) third-generation dual-source coronary CT angiography (CCTA) using a kVp-tailored contrast media injection protocol.
One hundred twenty patients (mean age = 62.6 years, BMI = 29.0 kg/m2) who underwent catheter angiography and CCTA with automated kVp selection were separated into two cohorts (each n = 60, mean kVp = 84 and 117). Contrast media dose was tailored to the kVp level: 70 = 40 ml, 80 = 50 ml, 90 = 60 ml, 100 = 70 ml, 110 = 80 ml, and 120 = 90 ml. Contrast-to-noise ratio (CNR) was measured. Two observers evaluated image quality and the presence of significant coronary stenosis (> 50% luminal narrowing).
Diagnostic accuracy (sensitivity/specificity) with ≤ 100 vs. > 100 kVp CCTA was comparable: per patient = 93.9/92.6% vs. 90.9/92.6%, per vessel = 91.5/97.8% vs. 94.0/96.8%, and per segment = 90.0/96.7% vs. 90.7/95.2% (all P > 0.64). CNR was similar (P > 0.18) in the low-kVp vs. high-kVp group (12.0 vs. 11.1), as ws subjective image quality (P = 0.38). Contrast media requirements were reduced by 38.1% in the low- vs. high-kVp cohort (53.6 vs. 86.6 ml, P < 0.001) and radiation dose by 59.6% (4.3 vs. 10.6 mSv, P < 0.001).
Automated tube voltage selection with a tailored contrast media injection protocol allows CCTA to be performed at ≤ 100 kVp with substantial dose reductions and equivalent diagnostic accuracy for coronary stenosis detection compared to acquisitions at > 100 kVp.
• Low-kVp coronary CT angiography (CCTA) enables reduced contrast and radiation dose.
• Diagnostic accuracy is comparable between ≤ 100 and > 100 kVp CCTA.
• Image quality is similar for low- and high-kVp CCTA.
• Low-kVp image acquisition is facilitated by automated tube voltage selection.
• Tailoring contrast injection protocols to the automatically selected kVp-level is feasible.
KeywordsCoronary CT angiography Diagnostic accuracy Tube voltage Radiation dose Contrast media dose
Compliance with ethical standards
The scientific guarantor of this publication is U. Joseph Schoepf, MD.
Conflict of interest
The authors of this manuscript declare relationships with the following companies: U. Joseph Schoepf is a consultant for and/or receives research support from Astellas, Bayer, Bracco, GE, Guerbet, Medrad, and Siemens. Katharina Otani is an employee of Siemens. Akos Varga-Szemes is a consultant for and/or receives research support from Guerbet and Siemens. Carlo N. De Cecco is a consultant for and/or receives research support from Guerbet and Siemens.
The authors state that this work has not received any funding.
Statistics and biometry
Katharina Otani, PhD, kindly provided statistical advice for this manuscript.
Written informed consent was waived by the Institutional Review Board.
Institutional Review Board approval was obtained.
• diagnostic study
• performed at one institution
- 3.Moscariello A, Takx RAP, Schoepf UJ et al (2011) Coronary CT angiography: image quality, diagnostic accuracy, and potential for radiation dose reduction using a novel iterative image reconstruction technique—comparison with traditional filtered back projection. Eur Radiol 21:2130–2138CrossRefPubMedGoogle Scholar
- 4.Jun BR, Yong HS, Kang E-Y et al (2012) 64-slice coronary computed tomography angiography using low tube voltage of 80 kV in subjects with normal body mass indices: comparative study using 120 kV. Acta Radiol Stockh Swed 1987 53:1099–1106Google Scholar
- 11.Layritz C, Schmid J, Achenbach S et al (2014) Accuracy of prospectively ECG-triggered very low-dose coronary dual-source CT angiography using iterative reconstruction for the detection of coronary artery stenosis: comparison with invasive catheterization. Eur Heart J Cardiovasc Imaging 15:1238–1245CrossRefPubMedGoogle Scholar
- 12.Modica MJ, Kanal KM, Gunn ML (2011) The obese emergency patient: imaging challenges and solutions. Radiogr Rev Publ Radiol Soc N Am Inc 31:811–823Google Scholar
- 19.Albrecht MH, Trommer J, Wichmann JL et al (2016) Comprehensive comparison of virtual monoenergetic and linearly blended reconstruction techniques in third-generation dual-source dual-energy computed tomography angiography of the thorax and abdomen. Invest Radiol. 51:582–590CrossRefPubMedGoogle Scholar
- 22.Menke J, Unterberg-Buchwald C, Staab W, et al (2013) Head-to-head comparison of prospectively triggered vs retrospectively gated coronary computed tomography angiography: Meta-analysis of diagnostic accuracy, image quality, and radiation dose. Am Heart J 165:154–163.e3.Google Scholar