能谱成像模式与传统前、后门控技术冠状动脉CT成像辐射剂量与图像质量的对比

目的对比宝石CT能谱成像（GSI）、传统前门控和后门控技术冠状动脉成像的辐射剂量及图像质量，探讨冠脉成像GSI扫描模式优势及临床应用价值。方法筛选2019年5月~2020年5月在我院成功完成CT冠状动脉成像患者162例，按照扫描模式分为3组:A组为GSI扫描模式，B组为后门控模式，C组为前门控模式。对比各组图像噪声、对比度、信噪比（SNR），对比噪声比（CNR）及图像优良指数（FOM），并计算比较各组间的有效放射剂量（ED）。结果图像质量比较:A组图像噪声明显低于后门控组及前门控组，差异具有统计学意义（P < 0.01）；A组SNR、CNR及FOM均明显高于后门控组（P < 0.01）及前门控组（P < 0.05）；C组SNR、CNR及FOM均高于B组，差异无统计学意义（P>0.05）。有效剂量比较:A组和C组ED均值分别为2.87±0.83、3.34± 2.36 mSv，明显低于B组（9.04±3.06 mSv）（P < 0.01)；A组和C组ED较B组分别降低68.25%和63.05%，而A组较C组降低约14.07%。结论宝石CT冠脉GSI扫描技术与后门控、前门控技术相比，不但能有效大幅度降低患者的辐射剂量，且能显著提高图像的质量，应在临床中积极推广应用。 

A radiation dose and image quality of coronary artery CT imaging comparison among the GSI model,the traditional front and back door control technique

ObjectiveTo explore the advantages and clinical value of coronary angiography in GSI scanning model by comparing the radiation dose and image quality among the GSI model, the traditional front and back door control technique.MethodsA total of 162 patients underwent successfully CT coronary angiography in our hospital from May 2019 to May 2020 were selected as research objects. According to the scanning model, these patients were divided into three groups. Group A was the GSI scanning mode, group B was the backdoor control mode and C group was the front door control mode. The image noise (SD), contrast, SNR (SNR), comparison of noise ratio (CNR), image quality index (FOM), and the effective radiation dose (ED) for these groups were compared.ResultsComparison of image quality: ① SD of A group was significantly lower than that of B group and C group (P < 0.01). ②SNR, CNR and FOM of Group A were significantly higher than B group (P < 0.01) and C group (P < 0.05). ③SNR, CNR and FOM of group C were higher than group B, but without significantly difference (P>0.05). Comparison of ED: ① The mean ED of group A and C were 2.87 ± 0.83 mSv, 3.34 ± 2.36 mSv, respectively, and were both significantly lower than group B (9.04 ± 3.06 mSv) (P < 0.01). ② ED in group A and group C decreased 68.25% and 63.05%, respectively, compared with group B, and ED in group A decreased by about 14.07% compared with group C.ConclusionCompared to the front and back door technique, GSI model scanning technology not only can effectively reduce the radiation dose, but also can significantly improve the quality of image, and it should be popularized in clinic.