广西医学

目的探讨低剂量联合全模型迭代重建应用于心房颤动患者左房肺静脉及心功能一站式检查的可行性。方法将行射频消融术的60例心房颤动患者随机分为试验组（30例）和对照组（30例），所有患者术前均行左房肺静脉CT血管造影检查。试验组扫描条件为管电压80 kV，管电流350 mA，采用全模型迭代算法重建；对照组扫描条件为管电压100 kV，管电流500 mA，采用迭代重建算法（iDose4）重建。比较两组的图像质量主观和客观评分、辐射剂量相关指标。分析试验组基于CT和超声测量的心功能指标的一致性。结果试验组的图像质量主观评分高于对照组（P＜0.05）。试验组左心房、降主动脉、右上肺静脉、右下肺静脉、左上肺静脉、左下肺静脉的噪声值低于对照组，对比度噪声比和信噪比高于对照组（P＜0.05）。试验组的容积CT剂量指数、剂量长度乘积、有效剂量低于对照组（P＜0.05），且上述指标的降低率分别为56.6%、 59.5%及59.6%。试验组基于CT和超声测量的左心室最大容积及左室射血分数的组内相关系数分别为0.896、0.912（P＜0.05），一致性较好。结论对于心房颤动患者，低剂量联合全模型迭代重建算法的一站式扫描方案在减少辐射剂量的同时，能够提高左房肺静脉的图像质量，并可较准确地评价心功能。

ObjectiveTo explore the feasibility of low dose combined with full model iterative reconstruction applied to one-stop examination of left atrial pulmonary vein and cardiac function in patients with atrial fibrillation. MethodsSixty patients with atrial fibrillation undergoing radiofrequency ablation were randomly divided into experimental group (30 cases) or control group (30 cases). All patients underwent CT angiography examination of left atrial pulmonary vein before operation. Scan conditions of the experimental group were as follows: tube voltage was 80 kV, tube current was 350 mA, and the full model iterative algorithm was used to reconstruct; in addition, scan conditions of the control group were as follows: tube voltage was 100 kV, tube current was 500 mA, and the iterative reconstruction algorithm (iDose4) was employed to reconstruct. The subjective and objective scores of image quality, and indices related to radiation dose were compared between the two groups. The consistency of cardiac function indices measured based on CT and ultrasound in the experimental group was analyzed. ResultsThe experimental group yielded a higher subjective score of image quality as compared with the control group (P＜0.05). The noise values of left atrium, descending aorta, right superior pulmonary vein, right inferior pulmonary vein, left superior pulmonary vein, left inferior pulmonary vein of the experimental group were lower than those of the control group, and contrast-to-noise ratio and signal-to-noise ratio were higher than those of the control group (P＜0.05). The experimental group exhibited lower volume CT dose index, dose-length product, and effective dose as compared with the control group (P＜0.05), and the reduction rates of indices as above were 56.6%, 59.5%, and 59.6%, respectively. The intra-class correlation coefficients of left ventricular maximum volume and left ventricular ejection fraction measured based on CT and ultrasound in the experimental group were 0.896 and 0.912 (P＜0.05), respectively, exerting favorable consistency. ConclusionFor patients with atrial fibrillation, one-stop scan regimen of low dose combined with full model iterative reconstruction algorithm can reduce radiation dose, and improve image quality of left atrial pulmonary vein at the same time; furthermore, it can evaluate cardiac function more accurately.