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目的 探讨Flash双源CT低管电压结合正弦图确定迭代重组(SAFIRE)技术对降低颞骨HRCT的辐射剂量的价值及其对图像质量影响. 方法 对临床因耳疾行HRCT扫描患者按时问先后顺序随机分为3组每组各30例.扫描管电压120kV,开启CARE Dose 4D及CARE kV技术,应用滤波反投影算法(FBP)重组;B组扫描管电压100 kV,开启CARE Dose 4D及CARE kV技术,应用SAFIRE(值为3)技术重组;C组扫描管电压100 kV,开启CAREDose 4D及CARE kV技术,应用FBP重组;由2名有经验的医师对3组图像质量[平均CT值、噪声(SD)、信号噪声比(SNR)、对比噪声比(CNR)、主观评分]及辐射剂量[容积CT剂量指数(CTDIvo1)、剂量长度乘积(DLP)、有效剂量(ED)]进行评价.结果 A 、B、C 3组CTDIvol分别为(36.26±3.69) 、(30.04±3.75)、(29.87±2.84) mGy;DLP分别为(180.83±26.1) 、(136.71 ±8.45)、(135.81±10.25) mGy·cm;ED分别为(0.41±0.15)、(0.31±0.21)、(0.30±0.18) mSv; SD(114.6±1.8)、(98.43±12.04)、(161.2±10.75) HU;SNR分别为(0.37 ±0.26)、(0.49±0.07) 、(0.32±0.10);CNR分别为(21.35±1.70) 、(26.99 ±2.30)、(17.67 ±3.13);A、B、C3组图像质量主观评分、平均CT值差异无统计学意义(p＞0.05),3组图像CTDIvol、DLP、ED、SD、SNR、CNR差异有统计学意义(P均＜0.05).结论 应用扫描管电压100 kV 、SAFIRE重组技术进行颞骨HRCT扫描,不仅能有效降低辐射剂量,还能优化射线剂量提高图像质量.“,”Objective To assess the value of Flash dual-source low tube kV CT scanning combined with sonogram-affirmed iterative reconstruction (SAFIRE) technique in reducing the radiation dose in the examination of temporal bone.Methods A total of 90 patients with clinically-suspected ear diseases were enrolled in this study.The patients were randomly divided into three groups according to the time sequence with 30 cases in each group.Patients of group A underwent temporal bone high resolution CT (HRCT) using 120 kV,CARE Dose 4D,CARE kV technique as well as FBP reconstruction technique.Patients of group B underwent temporal bone HRCT using 100kV,CARE Dose 4D,CARE kV technique as well as SAFIRE (value =3) reconstruction technique.Patients of group C underwent temporal bone HRCT using 100 kV,CARE Dose 4D,CARE kV technique as well as FBP reconstruction technique.The imaging qualities,including mean CT value,noise (SD),SNR,CNR,subjective evaluation score,CTDIvol,DLP and ED were evaluated by two experienced radiologists.The results were statistically analyzed.Results For group A,B and C,the value of CTDIvol was (36.26 ± 3.69),(30.04 ± 3.75) and (29.87 ± 2.84) mGy respectively ; the DLP was (180.83 ± 26.1),(136.71 ± 8.45) and (135.81 ± 10.25) mGy.em respectively; ED was (0.41 ±0.15),(0.31 ±0.21) and (0.30 ±0.18) mSy respectively;noise (SD) was (114.6 ± 1.8),(98.43 ± 12.04) and (161.2 ± 10.75) respectively ; SNR was (0.37 ± 0.26),(0.49 ± 0.07) and (0.32 ± 0.1 0) respectively ; and CNR was (21.35 ± 1.70),(26.99 ± 2.30) and (17.67 ± 3.13) respectively.No statistically significant differences in the subjective evaluation score and the mean CT value existed between each other among the three groups (P ＞ 0.05),while the differences in CTDIvol,DLP,ED,SD,SNR and CNR were statistically significant between each other among the three groups (P ＜ 0.05).Conclusion The use of 100 kV and SAFIRE reconstruction technique in HRCT scanning for temporal bone not only can significantly reduce radiation dose but also can improve the image quality.