团注追踪触发扫描技术支气管动脉CT血管造影触发阈值的优化

目的探讨团注追踪触发扫描触发阈值对支气管动脉CTA成像质量的影响;方法 60例经病理证实的肺癌患者行支气管动脉64层CT血管造影检查,将所以患者随机分为四组,各组触发阈值分别为80Hu、120Hu、160Hu、200Hu,其它扫描条件及方法各组相同,比较四组肺癌患者间增强后降主动脉、肺动脉、支气管动脉起始部CT值净增值、增强后主、肺动脉CT值差值及各组支气管动脉图像质量评分差异;结果增强后支气管分叉水平降主动脉、支气管动脉起始部CT值净增值各组之间差异均无显著性意义（p〉0.05）;增强后肺动脉CT值净增值及增强后主、肺动脉CT值差值之间差异有显著性意义（均以第3组最大,第4组最小）（p〈0.05）;而支气管动脉图像质量评分以第3组最高（p〈0.05）;结论团注追踪触发扫描支气管动脉CTA时,触发阈值与支气管动脉成像质量有关;选择合适的触发阈值可以明显提高支气管动脉成像质量。

The Optimization of Trigger Threshold in Bronchial Artery CT Angiography with Bolus Tracking Trigger Scanning Technology

Objective To investigate the effect of triggering threshold in bolus-tracking technique in bronchial artery CT angiography（CTA） imaging quality. Methods 60 patients with lung cancer confirmed by pathology were undertaken 64-slice spiral CT angiography. All the patients were randomly divided into four groups and the triggering threshold were 80 Hu, 120 Hu, 160 Hu and 200 Hu respectively, the other scanning conditions and methods of all groups are the same. In all the four groups, the CT values net added values, CT values difference values, the initiation site of bronchial artery and the differences of bronchial artery imaging quality score were compared after enhanced scanning; Results The CT values net added values were showed significant difference in descending aorta and the initiation site of bronchial artery after enhanced scanning in each group of lung cancer patients（p0.05）. However, the CT values net added values of pulmonary artery and CT values difference values between descending aorta and pulmonary artery were showed great significant difference（the highest in group 3 and the smallest in group 4）（p0.05）; the score of bronchial artery imaging quality was the highest in group 3（p0.05）. Conclusions Triggering threshold of Bolus-tracking technique is relevant with the imaging quality of bronchial artery CTA, appropriate triggering threshold can significantly improve the quality of bronchial artery imaging.