SAFIRE重建在超重患者双源CT冠状动脉成像中的临床应用

目的与传统滤波反投影（FBP）重建比较，评价管电压100kV下双源CT（dual．sourceCT，DSCT）基于原始数据的迭代重建（SinogramAffirmedkerativeReconstruction，SAFIRE）在超重患者冠状动脉成像的应用价值。方法将80例体重指数（bodymassindex，BMI）处于超重患者（男性：25kg／m2≤BMI〈30kg／m2；女性：24kg／rn2≤BMI〈29kg／m2）行双源cT冠状动脉成像患者按扫描，管电压随机分成A组（120kV）、B组（100kV），采用FBP重建，对B组采用SAFIRE重建得到C组图像。对三组的图像质量、平均CT值、图像噪声、信号噪声比（signal—to-noiseratio，SNR）、对比噪声比（contrast．to．noiseratio，CNR）及辐射剂量进行对比分析。结果三组图像质量分别为（3．51±0．70）分、（3．49±0．33）分和（3．55±0．47）分，差异无统计学意义（P〉0．05）；三组平均CT值、图像噪声、SNR及CNR比较差异均具有统计学意义（P〈0．05）；A组与B组（或C组）两组问平均CT值比较差异有统计学意义（P〈0．05），且A组平均CT值最低。B组与A组（或c组）两组间图像噪声、SNR及CNR比较差异有统计学意义（尸〈0．05），且A组较高。A、C两组间图像噪声、SNR及CNR比较差异无统计学意义（P〉0．05）；A、B组（或C组）辐射剂量比较差异有统计学意义（P〈0．05），且B组（或C组）较A组辐射剂量下降约34％。结论对于超重患者，采用100kV管电压结合SAFIRE行冠状动脉CTA检查，可改善图像质量，显著降低辐射剂量。

Application of sinogram affirmed iterative reconstruction on coronary artery angiography of overweight patients with dual-source CT

Objective To investigate the effects of Sinogram Affirmed Iterative Reconstruction （SAFIRE） on application value in coronary dual-source CT angiography comparing with regular filtered back projection （FBP）. Methods Dual-source CT coronary angiography was performed in 80 consecutive patients with a overweight BMI （male：25 kg/m2 ≤BMI〈30 kg/m2, female： 24 kg/m2 ≤BMI〈29 kg/m2）. Patients were randomized to using 120 kV （group A, n=40） and 100 kV （group B, n=40） with FBP, while the images of group B were rebuilt with SAFIRE and taken as group C. The difference between three groups in image quality, mean CT values, images noise, Signal-to-noise ratio, Contrast-to-noise ratio and radiation dose were compared. Results The mean image quality scores in patients scanned with three groups were （3.51 ± 0.70）, （3.49±0.33） and （3.55± 0.47）, there was no statistical difference between the three groups （P〉0.05）. The difference of the mean CT value, image noises and CNR was statistically significant between three groups （P〈0.05）. The difference of the mean CT value between group A and group B （or group C） was statistically significant （P〈0.05）, and group A was lowest. The difference of the image noises and CNR between group A （or group C） and group B was statistically significant （P 〈0.05）, and group A （or group C） was higher. The difference of the effective radiation dose between group A and group B （or group C） was statistically significant （P〈0.05）, and group B（or group C） decreased radiation dose of about 34% than group A. Conclusion Using 100 kV tube voltage and SAFIRE scan protocol with dual-source CT coronary angiography is feasible in patients with overweight BMI. The scan protocol can substantially reduce radiation doses while preserve good diagnostic image quality.