CT不同成像方式在肺动脉血管成像中对辐射剂量及图像质量的影响

摘要

目的 探讨CT不同成像方式在肺动脉血管成像(Computer Tomography Angiography,CTA)中对辐射剂量及图像质量的影响.方法 选取2016年9月至2017年8月间于我院检查的初步怀疑为肺动脉栓塞的患者共计100例,将患者根据随机数字表法分为4组,每组各25例.组1选用低管电压Flash模式;组2选用高管电压Flash模式;组3选用80/sn140 kV双能量扫描;组4选用100/sn 140 kv双能量扫描.对获得的图像进行主观图像质量评分,并且测量各组患者肺动脉干CT值、信噪比(Signal Noise Ratio,SNR)、载噪比(Carrier Noise Ratio,CNR)、CT容积计量指数(CTDIvol)、剂量-长度乘积值(DLP)及有效剂量(Effective Dose,ED).结果 四组图像主观评分结果差异无统计学意义(t=-1.043,P＞0.05);各组的肺动脉主干CT值、SNR、CNR值均无统计学差异(P＞0.05);比较各组患者的CTDIvol、DLP、ED值,可得出各组患者接受的辐射剂量存在统计学差异(P＜0.01),其中组1接受辐射剂量最小,组4接受辐射剂量最大.结论 双源CT在肺动脉CTA中应用效果良好,其中低管电压Flash辐射剂量最低,值得进一步推广使用.%Objective The purpose of this paper is to explore the dual-source CT different imaging methods in the pulmonary artery angiography (CTA) of the influence of radiation dose and image quality. Methods A total of 100 patients who were preliminary suspected with pulmonary embolism in our hospital were included in this stuudy between September 2016 and August 2016. These patients were randomly divided into four groups according to number table method with 25 in each group (n=25). The low voltage Flash mode, executives voltage Flash mode, 80/sn 140 kV double energy scanning, and 100/sn140 kV double energy scanning were respectively used in the four groups. Besides, the image of the subjective image quality score, and measure the groups of patients with pulmonary CT value, SNR, CNR, CTDIvol, DLP and ED were obtained. Results There were no significant differences for image subjective ratings among the four groups (t=1.043, P＞1.043). The between groups of pulmonary artery trunk CT value, SNR, CNR were no statistically significant difference (P＞0.05). The CTDIvol, DLP, ED values were significantly statistical different between the four groups (P＜0.01), in which the group 1 accepted minimum radiation dose, and group 4 accepted the highest radiation dose. Conclusion Dual-source CT imaging can provid the powerful basis for diagnosis, lower tube voltage Flash and the lowest radiation dose, which is worth for further clinical use.