Comparison of "one-stop" coronary and head-and-neck computed tomography angiography with different scan sequences using a wide-detector system: heart-to-cranial vs. cranial-to-heart.

Abstract

Background: "One-stop" coronary computed tomography angiography (CCTA) and head-and-neck computed tomography angiography (HNCTA) use heart-to-cranial or cranial-to-heart protocols with a wide-detector system. It is not yet known whether the HNCTA and CCTA scanning sequence affect the image quality. This study aimed to evaluate the image quality of one-stop computed tomography angiography (CTA) using two different protocols.

Methods: A total of 150 patients were included in this case-control study, and divided into three groups (A, B, and C; n=50 each). Patients in groups A and B underwent one-stop CTA scans, with CCTA completed first in group A and HNCTA completed first in group B, while patients in group C underwent separate HNCTA and CCTA scans. The subjective image quality score and objective image quality measurements [computed tomography (CT) attenuation, contrast-to-noise ratio (CNR), and signal-to-noise ratio (SNR) for the vessels] of the groups were compared. The CT attenuation of the right atrium (RA), confluence of sinuses (CS), and internal jugular vein (IJV) were measured to evaluate the visualization.

Results: There were no statistically significant differences between groups A and B (which received one-stop CTA) in terms of HNCTA, except for the SNR at the internal carotid artery, and the CNR at the common carotid artery. The percentages of coronary segments with assessable quality in groups A, B, and C were 99.17%, 97.50%, and 98.86%, respectively. There were no statistically significant differences in the objective measurements between groups A and B, except for the CT values at the left anterior descending artery, and left circumflex artery. Group B had the lowest CT attenuation values for the RA, IJV, and CS (P<0.05). The effective doses of groups A and B (which received one-stop CTA) were lower than that that of group C (which received separate HNCTA and CCTA scans).

Conclusions: Using a wide-detector CT system, one-stop CCTA and HNCTA can provide images of the carotid, cerebral, and coronary arteries. Performing HNCTA before CCTA scanning can effectively reduce the residual contrast in the RA and the visualization in veins.