Radiation dose and image quality of computed tomography of the supra-aortic arteries: A comparison between single-source and dual-source CT Scanners

Purpose: The purpose of this work was to compare the image quality and radiation dose delivered to patients during computed tomography (CT) angiography (CTA) of the supra-aortic arteries using two single-source (SS) and two dual-energy (DE) CT scanners. Material and methods: In this retrospective study, 120 patients who underwent CTA of supra-aortic arteries were studied using four different types of CT scanners: a sixteen and forty-detector-row SS and two DE CT scanners. Seventy milliters of contrast medium were injected at a flow rate of 4 mL/s using a power injector. For each patient the dose-length product (DLP), the volume computed tomography dose index (CDTIvol), the length of the scan and the effective dose (ED) were calculated. Qualitative and quantitative [image noise, signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR)] image quality assessment was performed. Results: A statistically significant lower value of the DE compared to the SS technology (P < 0.0001) for the CDTI, DLP and ED was found, whereas we did not find any statistically significant difference between the four scanners for the measurements of the image noise, SNR and CNR. Conclusion: DS CT scanners allow performing CTAs with a reduced dose compared to SS CT scanner with comparable image quality.