Application of bolus tracking: The effect of ROI positions on the images quality of cervicocerebral CT angiography

Huiming Wu; Jianhua Wang; Maodong Zhou; Yajie Wang; Can Cui; Changsheng Zhou; Xiao Chen; Zhongqiu Wang

doi:10.1016/j.heliyon.2024.e29260

Application of bolus tracking: The effect of ROI positions on the images quality of cervicocerebral CT angiography

Heliyon. 2024 Apr 4;10(7):e29260. doi: 10.1016/j.heliyon.2024.e29260. eCollection 2024 Apr 15.

Authors

Huiming Wu¹, Jianhua Wang¹, Maodong Zhou¹, Yajie Wang¹, Can Cui¹, Changsheng Zhou², Xiao Chen¹, Zhongqiu Wang¹

Affiliations

¹ Department of Radiology, The Affiliated Hospital of Nanjing University of Chinese Medicine, 155 Hanzhong road, Nanjing, 210029, China.
² Department of Radiology, Jinling Hospital Nanjing University, 305 Zhongshan East road, Nanjing, 210029, China.

Abstract

Background: Cervicocerebral CT angiography (CTA) using the bolus tracking technique has been widely used for the assessment of cerebrovascular diseases. Regions of interest (ROI) can be placed in the descending aorta, ascending aorta, and the aortic arch. However, no study has compared the arteries and veins display when when the region of interest (ROI) is placed at different sites. In this study, we showed the impact of ROI positions on the image quality of cervicocerebral CTA.

Methods: Two hundred and seventy patients who underwent cervicocerebral CTA with bolus tracking technique were randomly divided into three groups based on the position of the ROI placement: ascending aorta (Group 1, n = 90), aortic arch (Group 2, n = 90), and descending aorta (Group 3, n = 90). The scanning parameters and contrast agent injection protocols were consistent across all groups. Three observers independently assessed the objective image quality, while two observers jointly assessed the subjective image quality using a grade scale: poor (grade 1), average (grade 2), good (grade 3), and excellent (grade 4). The differences in intravascular CT values, signal-to-noise ratio (SNR), contrast-to-noise ratio (CNR), AVCR (arterial venous contrast ratio), and subjective image quality scores were compared among the three groups.

Results: The CT values of the intracranial veins (superior sagittal sinus, ethmoid sinus and great cerebral vein) in group 1 were significantly lower than those in group 3 (p < 0.001). However, no significant differences were observed in CT values, SNR and CNR in the internal carotid artery and middle cerebral artery among the three groups. The proportion of images with grade 4 was significantly higher in group 1 than group 2 and 3 (41.1% vs 15.6% and 13.3%, p < 0.001). The proportion of images with grade 1 was significantly lower in group 1 than group 2 and 3 (1.1% vs 6.6% and 17.8%, p < 0.001).

Conclusion: The ROI positions for cervicocerebral CTA did not affect the arterial image quality, but venous structures imaging was affected when the ROI was placed in the ascending aorta.

Keywords: Bolus tracking; CT angiography; Head and neck; Region of interest.