Investigating the Effects of the kV Assist Technique on Image Quality and the Reduction of Effective Dose and Carcinogenic Risk of Coronary Computed Tomography Angiography

Document Type : Original Article (s)



Background: The aim of this study was to evaluate the effects of the kV Assist technique on the radiation dose and image quality of coronary computed tomography angiography (CCTA).
Methods: In this retrospective case-control study, 179 patients with the mean age of 58.45±11.86 years, who had undergone CCTA test using the kv assist technique, were considered as the study group; and 141 patients with the mean age of 58.24±11.37 years, who had previously undergone CCTA with the usual 120 kV protocol, were considered as the control group. The two groups were compared in terms of image quality criteria including noise, contrast-to-noise ratio, signal-to-noise ratio, CT numbers of the left coronary artery, and left ventricular chamber, and radiation dose criteria including effective dose and carcinogenic risk.
Results: The effective dose (5.05 ± 2.16 vs. 6.63 ± 3.04 mSv; P < 0.001) and overall risk of carcinogenesis (3.89 ± 1.63 vs. 5.11 ± 2.71 in 10,000 people; P < 0.001) reduced by about 23%in the study group compared to the control group. No significant differences were observed between the two groups in terms of noise, signal-to-noise ratio, and left coronary artery CT number (P > 0.050). Left ventricular chamber CT number and contrast to noise ratio were higher in the study group than the control group (P < 0.001).
Conclusion: Using the kV Assist technique can reduce the effective dose and the carcinogenic risk of CCTA without loss of image quality.


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