关键词: 辐射, 图像质量, 电子计算机断层扫描, 冠脉血管, 重建技术

Abstract:

Objective: To dissuss the feasibility of the application of iDose⁴ to improve image quality and reduce the radiation dose in coronary artery CT angiography(CCTA)compared with traditional filter back-projection(FBP).Methods: A total of 60 patients under went 256-slice spiral CT coronary angiography were randomly divided into two groups, 30 cases in each group. In one group 120 kV tube voltage was used,and FBP (FBP-120 kV group) and iDose⁴ (iDose⁴-120 kV group) reconstruction were performed. In another group, 100 kV tube voltage and iDose⁴ technique reconstruction(iDose⁴-100 kV group) were used. The image quality in FBP-120 kV group compared with iDose⁴-120 kV group and iDose⁴-100kV group.The radiation doses in FBP-120 kV and iDose⁴-100 kV groups were also compared.Results: The average score of image quality in FBP-120 kV group was (3.29±0.61) points, and was (3.43±0.51) points in iDose⁴-120 kV,there was no significant difference between them (t=-1.47, P=0.17).The mean image quality score in iDose⁴-100 kV group was(3.21±0.43)points, and threre was no statistical difference compared with FBP-120 kV group(t=0.58,P=0.58). The signal to noise ratio(SNR) and contrast to noise ratio(CNR) in iDose⁴-120 kV group were higher than those in FBP-120 kV group(P<0.01). The SNR and CNR in iDose⁴-100 kV group had no significant differences compared with FBP-120 kV group (P>0.15). The effective dose in iDose⁴-100 kV group was significantly lower than that in FBP-120 kV group (P<0.001).Conclusion: In CT imaging of coronary artery, compared with FBP, iDose⁴ technology can improve the quality of image and appropriately reduce the tube voltage under the condition of guaranting the quality of image,and it can reduce the radiation dose.

Key words: radiation, image quality, computed tomography, coronary angiography, reconstruction technique