Clinical value and feasibility of CT pulmonary angiography with personalized injection of contrast agent in pulmonary embolism

Abstract

Objective: To determine the clinical value and feasibility of CT pulmonary angiography (CTPA) with personalized injection of contrast agent in pulmonary embolism (PE).

Methods: In the present retrospective study, 130 patients who underwent CTPA examination in our hospital from June 2019 to May 2020 were evaluated. Among them, 67 cases were detected by CTPA with personalized injection of contrast agent as the observation group (Obs group), and 63 cases were detected by CTPA with bolus-tracking (BT) as the control group (Con group). The specificity, sensitivity and accuracy of the detection in the two groups were compared. The image quality score and superior vena cava artifact score of the two diagnostic methods were compared. Additionally, the volumetric CT dose index (CTDIvol) and dose length product (DLP) of the two groups were compared.

Results: The Obs group yielded a significantly higher specificity in diagnosing PE than the Con group (P<0.05), but there were no significant differences between the two groups in the sensitivity and accuracy (P>0.05). The image quality score and superior vena cava artifact score of the two groups were not significantly different (P>0.05), and the Obs group showed significantly lower CTDIvol and DLP than the Con group (P<0.05).

Conclusion: CTPA with personalized injection of contrast agent has good diagnostic value for PE, with good imaging effect and safe profile, and has a lower radiation dose requirement.

Keywords: CTPA; Personalized injection of contrast agent; diagnose; pulmonary artery embolism.

Figure 1

Image of a 67-year-old male patient. (A) The volume rendering (VR) of pulmonary artery. (B-D) The maximum density projection (MIP) of transverse, coronal and sagittal positions respectively. (A-D)shows that the branches of pulmonary artery at all levels were well displayed, the pulmonary vein was lightly developed, there was no hardening artifact of superior vena cava contrast agent, the image quality was good, and multiple thrombi in the upper lobe of the right lung were found.

Figure 2

The patient, a 73-year-old male, was re-examined after pulmonary embolism treatment. (A) the pulmonary artery volume reconstruction (VR) diagram, and (B-D) the maximum density projection (MIP) diagrams of transverse, coronal and sagittal positions respectively. (A-D) All branches of the pulmonary artery were fully developed, the contrast agent was filled evenly, and the pulmonary vein was lightly developed. There was no hardening artifact of the superior vena cava contrast agent, and the image quality was good.

Figure 3

Comparison of CT values of vascular enhancement between the two groups. A. The two groups had no notable difference in the enhanced CT value of pulmonary artery trunk (t=1.218, P=0.225). B. The two groups had no notable difference in the enhanced CT value of left pulmonary artery (t=0.959, P=0.340). C. The two groups had no notable difference in the enhanced CT value of right pulmonary artery (t=1.429, P=0.155). D. The two groups had no notable difference in the enhanced CT value of pulmonary artery (t=1.816, P=0.072).

Figure 4

Comparison of radiation dose between the two groups. A. The Obs group showed significantly lower CTDIvol than the Con group (t=4.533, P<0.001). B. The Obs group showed significantly lower DLP than the Con group (t=5.679, P<0.001). Note: ***means P<0.001.