基于时间-密度曲线的改进的个性化肺动脉CTA扫描方案研究

Study on Improved Individualized Pulmonary Artery CTA Scanning Scheme Based on Time-Density Curve

目的利用时间-密度曲线探讨个性化肺动脉CT血管造影扫描的最佳扫描方法。方法随机分组,对照组(n=23)采用智能跟踪造影方法,实验组(n=25)采用小剂量团注,测量肺动脉干和肺静脉(或左心室)两处的达峰时间,设定正式扫描的启动时间为肺动脉达峰时间,调整序列参数,使扫描的总时间小于两点达峰时间的差值。采用盲评法对图像质量进行评价,对图像的优良率采用SPSS 25.0进行统计分析。结果智能跟踪造影方法的图像优良率为73.9%,基于时间密度曲线的个性化扫描方法的图像优良率为96%,二者之间差异显著(P=0.030)。结论基于时间-密度曲线,将增强序列的延迟时间设为肺动脉的峰值时间,扫描时间控制在肺动脉达峰时间与肺静脉达峰时间的差值之内的个性化扫描方法,可以获得优良的图像质量,提高了病灶检出率。

Objective To explore the optimal scanning method of personalized pulmonary artery CT angiography scanning using the time-density curve.Methods All patients were randomly divided into two groups.The control group(n=23)was treated with smart tracking angiography,and the experimental group(n=25)was treated with low dose bolus injection.The peak time of pulmonary trunk and pulmonary vein(or left ventricle)was measured.Pulmonary artery peak time was set as the start time of scanning.The sequence parameters were adjusted so that the total scan time is less than the difference between the two peak times.Blind evaluation method was used to evaluate the image quality,and SPSS 25.0 was used to statistically analyze the optimal rate of the image.Results The optimal rate of images obtained by the smart tracking angiography was 73.9%,while that obtained by the individualized scanning method based on the time-density curve was 96%,showing a significant difference(P=0.030).Conclusion The individualized scanning method,which sets the delay time of contrast sequence to the peak time of pulmonary artery and controls the scanning time within the difference between the peak time of pulmonary artery and pulmonary vein,can obtain excellent image quality and improve the detection rate of pulmonary lesions.