64层螺旋CT触发阈值对肺静脉成像质量的影响

Influence of Different Trigger Thresholds of 64-Slice Spiral CT on Imaging Quality of Pulmonary Vein

目的比较不同触发阈值下肺静脉成像质量,以期获得肺静脉成像最佳触发阈值。方法选择射频消融术前进行肺静脉CT成像患者60例,随机均分为3组,触发阈值分别设为80、100、120HU,评价不同组别肺静脉成像质量,同时比较肺静脉、肺动脉、左心房强化CT值以及肺静脉与肺动脉强化CT差值的组间差异。结果三组患者肺静脉成像质量评分有统计学差异(P<0.01),肺静脉、肺动脉、左心房强化CT值以及肺静脉与肺动脉强化CT差值有显著性差异(P<0.05)。三组患者组间两两比较图像质量和强化CT值均有统计学差异。结论以左心房中部为监测点,阈值设为120HU时肺静脉成像质量更佳。

Objective To compare the quality of pulmonary vein imaging with different tracking thresholds in order to obtain the best threshold.Methods A total of 60 patients who underwent pulmonary venous CT imaging before radiofrequency ablation were randomly divided into three groups.The trigger thresholds were set to 80,100 and 120 HU,respectively.The quality of pulmonary venography was evaluated in different groups.Intergroup differences in enhanced CT values of pulmonary vein, pulmonary artery and left atrium were evaluated.The difference of enhanced CT values between pulmonary veins and pulmonary arteries among groups were also compared.Results The pulmonary vein imaging quality scores of the three groups were statistically different (P<0.01).The enhanced CT values of pulmonary vein,pulmonary artery,left atrial and difference between the pulmonary vein and the pulmonary artery were statistically different (P<0.05).There were significant differences in image quality and enhanced CT values among the three groups.Conclusion Taking left atrium as monitoring point,the imaging quality of pulmonary vein is bett er when the threshold value is set to 120 HU.