High-pitch computed tomography pulmonary angiography with iterative reconstruction at 80 kVp and 20 mL contrast agent volume

• Published in: European radiology Vol. 24; no. 12; pp. 3260 - 3268
• Main Authors: Lu, Guang Ming, Luo, Song, Meinel, Felix G., McQuiston, Andrew D., Zhou, Chang Sheng, Kong, Xiang, Zhao, Yan E., Zheng, Ling, Schoepf, U. Joseph, Zhang, Long Jiang
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Springer Berlin Heidelberg 01.12.2014; Springer Nature B.V
• Subjects: Accuracy; Algorithms; Angiography - methods; Chest; Contrast agents; Contrast Media; Diagnosis, Differential; Diagnostic Radiology; Feasibility Studies; Female; Humans; Image Processing, Computer-Assisted - methods; Imaging; Internal Medicine; Interventional Radiology; Male; Medical imaging; Medicine; Medicine & Public Health; Middle Aged; Neuroradiology; Prospective Studies; Pulmonary arteries; Pulmonary Artery - diagnostic imaging; Pulmonary Embolism - diagnostic imaging; Pulmonary embolisms; Radiation; Radiation Dosage; Radiology; Reproducibility of Results; ROC Curve; Tomography; Tomography, X-Ray Computed - methods; Ultrasound; Berlin Germany; Germany; Computed tomography pulmonary angiography; Computed tomography; Low tube voltage; Iterative reconstruction; Contrast material
• DOI: 10.1007/s00330-014-3365-9
• ISSN: 0938-7994

Objectives To evaluate the image quality, radiation dose and diagnostic accuracy of 80kVp, high-pitch CT pulmonary angiography (CTPA) with iterative reconstruction using 20 ml of contrast agent. Methods One hundred patients with suspected pulmonary embolism (PE) were randomly divided into two groups ( n  = 50 each; group A, 100 kVp, 1.2 pitch, 60 ml of contrast medium and filtered back projection algorithm; group B, 80 kVp, 2.2 pitch, 20 ml of contrast medium and sinogram affirmed iterative reconstruction). Image quality, diagnostic accuracy and radiation dose were evaluated and compared. Results Mean CT numbers of pulmonary arteries in group B were higher than those in group A (all P  < 0.001). Contrast-to-noise ratio and signal-to-noise ratio of group B were higher than those of group A (both P  < 0.001). There was no significant difference in subjective image quality scores between two groups ( P  = 0.807). The interobserver agreement was excellent (k = 0.836). There was no significant difference in diagnostic accuracy between the two groups ( P  > 0.05). Compared with group A, radiation dose of group B was reduced by 50.3 % ( P  < 0.001). Conclusions High-pitch CTPA at 80 kVp can obtain sufficient image quality in normal-weight individuals with 20 ml of contrast agent and half the radiation dose of a conventional CTPA protocol. Key Points • CTPA is feasible at 80 kVp using only 20 ml of contrast agent. • High-pitch CTPA at 80 kVp has an effective dose under 1 mSv. • This CTPA protocol can obtain sufficient image quality in normal-weight individuals.