Abstract：Objective: To evaluate image quality and radiation dose of dual-energy scanning protocol and conventional scanning protocol(single-energy scanning) with dual-source CT in pulmonary angiography and to investigate the optimal scanning protocols of dual-source CT pulmonary angiography. Methods: Two hundred and thirty-five patients with clinically suspected pulmonary embolism underwent flash dual-source CT pulmonary angiography were collected, and divided into three groups: group A(DE, 80/Sn140 kV)(n=77); group B(DE, 100/Sn140 kV)(n=80); group C(tube voltage was selected automatically by Care kV)(n=78). The CT attenuation values of pulmonary arteries(grade 1～3) and dorsal muscle, and background noise were measured. Corresponding signal to noise ratio(SNR) and contrast to noise ratio(CNR) were calculated. Meanwhile, two experienced radiologists assessed the image quality of the three groups. Image quality and radiation exposure were compared between groups, and P<0.05 was considered statistically significant. Results: CT attenuation values in bilateral upper lobe pulmonary artery have no difference significantly(P>0.05) between group A and group B/C. The value of the group B was lower than that of in group C(P<0.05), there was no significant difference(P>0.05) in others compares. Compared to the other of two groups, image noise in group A were higher than others, and while its corresponding CNR and SNR for all measured pulmonary arteries were lower than others group(P<0.05). The image quality meet the diagnostic requirements for pulmonary embolism in all groups, and the image quality score of three groups has no statistically significant difference(P>0.05) with good interobserver agreement. The image quality with good to excellent(1～2 score) grade of all subjective was more than 90%, and no significantly difference was between the groups(P>0.05). The values of CTDIvol, DLP, and ED were significantly lower in group A than that in group B and group C(P＜0.05), and the mean ED values of group A was lower 46.8% than that of group C. Conclusion: Compared with conventional scanning protocol in dual-source CTPA, the dual-energy scanning protocol (80/Sn140 kV) with the diagnostic image quality allows a significant radiation dose reductions.
罗显丽，李邦国，刘 盼，孙 辉，黄婷婷，王 梦，张雪梅. 双源CT肺动脉成像双能量与单能量扫描的图像质量及辐射剂量[J]. 中国临床医学影像杂志, 2017, 28(2): 140-144.
LUO Xian-li, LI Bang-guo, LIU Pan, SUN Hui, HUANG Ting-ting, WANG Meng, ZHANG Xue-mei. Image quality and radiation dose of dual-energy scanning and single-energy scanning with#br#
dual-source CT in pulmonary angiography. JOURNAL OF CHINA MEDICAL IMAGING, 2017, 28(2): 140-144.
[1]Konstantinides SV, Torbicki A, Agnelli G, et al. 2014 ESC guidelines on the diagnosis and management of acute pulmonary embolism[J]. Eur Heart J, 2014, 35(43): 3033-3069.
[2]Okada M, Kunihiro Y, Nakashima Y, et al. Added value of lung perfused blood volume images using dual-energy CT for assessment of acute pulmonary embolism[J]. Eur J Radiol, 2015, 84(1): 172-177.
[3]Zhang LJ, Wang ZJ, Zhou CS, et al. Evaluation of pulmonary embolism in pediatric patients with nephrotic syndrome with dual energy CT pulmonary angiography[J]. Acad Radiol, 2012, 19(3): 341-348.
[4]Bauer RW, Frellesen C, Renker M, et al. Dual energy CT pulmonary blood volume assessment in acute pulmonary embolism-correlation with D-dimer level, right heart strain and clinical outcome[J]. Eur Radiol, 2011, 21(9): 1914-1921.
[5]Bauer RW, Kramer S, Renker M, et al. Dose and image quality at CT pulmonary angiography comparison of first and second generation dual-energy CT and 64-slice CT[J]. Eur Radiol, 2011, 21(10): 2139-2147.
[6]De Zordo T, von Lutterotti K, Dejaco C, et al. Comparison of image quality and radiation dose of different pulmonary CTA protocols on a 128-slice CT: high-pitch dual source CT, dual energy CT and conventional spiral CT[J]. Eur Radiol, 2012, 22(2): 279-286.
[7]Kumamaru KK, Hunsaker AR, Kumamaru H, et al. Correlation between early direct communication of positive CT pulmonary angiography findings and improved clinical outcomes[J]. Chest, 2013, 144(5): 1546-1554.
[8]Raja AS, Ip IK, Prevedello LM, et al. Effect of computerized clinical decision support on the use and yield of CT pulmonary angiography in the emergency department[J]. Radiology, 2012, 262(2): 468-474.
[9]Hurwitz LM, Reiman RE, Yoshizumi TT, et al. Radiation dose from contemporary cardiothoracic multidetector CT protocols with an anthropomorphic female phantom: implications for cancer induction[J]. Radiology, 2007, 245(3): 742-750.
[10]戴颖钰，马新星，陈铟铟，等. 四种CT扫描模式对肺动脉成像图像质量和辐射剂量的影响[J]. 中国医学影像学杂志，2015，23（1）：4-9.
[11]Co SJ, Mayo J, Liang T, et al. Iterative reconstructed ultra high pitch CT pulmonary angiography with cardiac bowtie-shaped filter in the acute setting: effect on dose and image quality[J]. Eur J Radiol, 2013, 82(9): 1571-1576.
[12]McLaughlin PD, Liang T, Homiedan M, et al. High pitch, low voltage dual source CT pulmonary angiography: assessment of image quality and diagnostic acceptability with hybrid iterative reconstruction[J]. Emerg Radiol, 2015, 22(2): 117-123.
[13]康绍磊，曾宪春，谢晓洁，等. 智能最佳管电压扫描联合自动管电流调节技术降低成人胸部CT扫描辐射剂量[J]. 中国医学影像技术，2013，29（4）：636-640.
[14]Reimann AJ, Davison C, Bjarnason T, et al. Organ-based computed tomographic(CT) radiation dose reduction to the lenses: impact on image quality for CT of the head[J]. J Comput Assist Tomogr, 2012, 36(3): 334-338.
[15]Ramadan SU, Kosar P, Sonmez I, et al. Optimisation of contrast medium volume and injection-related factors in CT pulmonary angiography: 64-slice CT study[J]. Eur Radiol, 2010, 20(9): 2100-2107.
[16]王杰，曾勇明，彭刚，等. SAFIRE重建算法对胸部CT图像质量和辐射剂量的影响[J]. 中国医学影像技术，2013，29（1）：1896-1990.
[17]Pontana F, Henry S, Duhamel A, et al. Impact of iterative reconstruction on the diagnosis of acute pulmonary embolism(PE) on reduced-dose chest CT angiograms[J]. Eur Radiol, 2015, 25(4): 1182-1189.
