全模型迭代重建算法(FIRST)在低剂量冠状动脉CTA中的应用研究  

Application of Forward Projected Model-Based Iterative Reconstruction Solution in Low-Dose Coronary CTA

作　　者：王明[1] 马壮飞 朱亚新 王沄[1] 付海鸿[1] 王怡宁[1] 金征宇[1] WANG Ming;MA Zhuangfei;ZHU Yaxin;WANG Yun;FU Haihong;WANG Yining;JIN Zhengyu(Department of Radiology,Peking Union Medical College Hospital,Beijng 100730,China;Canon Medical System(China)Co.,Ltd.,Beijing 100015,China)

机构地区：[1]中国医学科学院北京协和医院放射科,北京100730 [2]佳能医疗系统(中国)有限公司,北京100015

出　　处：《中国医疗设备》2021年第11期90-93,115,共5页China Medical Devices

摘　　要：目的探讨全模型迭代重建算法(Forward Projected Model-Based Iterative Reconstruction Solution,FIRST)在80 kV低剂量冠状动脉CT血管造影(CT Angiography,CTA)中的应用价值。方法本研究纳入了45例使用Aquilion ONE GENESIS 640层CT行80 kV低剂量冠状动脉CTA扫描的患者,平均体质指数为(24.7±2.7)kg/m^(2),心率小于75次/min。扫描原始数据分别采用FIRST_Cardiac、混合迭代算法和滤波反投影算法进行重建。测量主动脉根部,左主干,前降支近、中、远段,回旋支近、远段及右冠状动脉近、中、远段的管腔及邻近脂肪成分CT值及图像噪声标准差(Standard Deviation,SD),并计算信噪比(Signal to Noise Ratio,SNR)和对比噪声比(Contrast to Noise Ratio,CNR)。右冠状动脉、前降支和回旋支的CT值和SD值为近、中、远段的平均值。双盲法下对冠脉18个节段采用4分法进行图像质量评估。对每一个患者进行剂量长度乘积和CT容积剂量指数的记录并进行有效辐射剂量的测算。结果三组重建图像在右冠状动脉、前降支、回旋支、主动脉根部和左主干的CT值无明显差异(P=0.071、0.081、0.061、0.263、0.409);FIRST_Cardiac组图像的SD值均明显低于其余两组(P<0.001);FIRST_Cardiac组图像的SNR和CNR以及主观图像质量评分均明显高于其余两组(P<0.001)。结论FIRST能够显著降低80 kV低剂量冠状动脉CTA的图像噪声,提高图像质量,满足临床诊断需求。Objective To investigate forward projected model-based iterative reconstruction solution(FIRST)in low-dose coronary CTA.Methods Forty five patients with 80 kV low-dose coronary CTA scanning using Aquilion ONE GENESIS 640 slices CT were included in this study.The mean body mass index was(24.7±2.7)kg/m^(2),and the heart rate was less than 75 beats/min.The original scanned data were reconstructed by FIRST_Cardiac,adaptive iterative dose reduction 3D and filtered back projection algorithm.The value of CT value and image noise standard deviation(SD)of lumen and adjacent fat components were measured in aortic root,left main artery,proximal,middle and distal anterior descending branch,proximal and distal circumconvolutional branch,and proximal,middle and distal segments of right coronary artery,and signal to noise ratio(SNR)and contrast to noise ratio(CNR)were calculated.CT and SD values of right coronary artery,anterior descending artery and circumflex artery were calculated by averaging the proximal,middle and distal segments.Double blind method was used to evaluate the image quality of 18 segments of coronary artery by 4-point method.Dose-length product and CT volumetric dose index were recorded and the effective radiation dose was measured.Results There were no significant differences in CT values of right coronary artery,anterior descending artery,circumflex artery,aortic root and left main artery among the three groups(P=0.438,0.280,0.292,0263 and 0.409,respectively).The SD values of FIRST_Cardiac images were significantly lower than those of the other two groups(P<0.001).SNR,CNR and subjective image quality scores of FIRST_Cardiac images were significantly higher than those of the other two groups(P<0.001).Conclusion FIRST can significantly reduce the image noise of 80 kV low-dose coronary CTA,improve image quality,and satisfy the clinical diagnosis.

关 键 词：全模型迭代算法 冠状动脉CTA 低辐射剂量 图像质量 

分 类 号：R543.3[医药卫生—心血管疾病] R814.42[医药卫生—内科学]