基于256层CT的老年患者自由呼吸状态下冠状动脉成像质量的研究

Study on the imaging quality of 256-slice coronary CT angiography in elderly patients with free breathing

目的评价老年患者自由呼吸和屏气后扫描在256层CT冠状动脉成像中的图像质量。方法选取2020年6月-2020年12月间在复旦大学附属华东医院行冠状动脉CT血管造影的受检者106例,随机将受检者分为试验组和对照组,试验组(n=53)行自由呼吸下(Coronary CTAngiography,CCTA),对照组(n=53)行屏气后CCTA。同时将75次/分作为快心率组和慢心率组的指标进行分组。记录各组的BMI、心率、图像CT值平均数、噪声(SD),根据公式计算信噪比(SNR)与对比噪声比(CNR);由2名高年资放射科医师采用双盲法对图像进行评价,记录冠状动脉分支的病变情况,并对各项指标进行统计学分析。结果试验组和对照组在主动脉弓根部及冠状动脉近端的图像的信噪比分别为(17.78±3.08)、(29.89±5.68)、(18.12±3.17)、(28.98±4.92),对比噪声比分别为(14.40±2.71)、(24.28±4.90)、(14.47±2.88),(22.94±4.06),2组差异无统计学意义(P>0.05).试验组与对照组客观图像评价差异无统计学意义(P>0.05)。结论通过对比受检者自由呼吸状态和屏气后的冠状动脉图像主客观分析,可根据受检者配合情况,选择自由呼吸状态进行冠状动脉CT血管造影,提高受检者的图像质量。

Objective To evaluate the image quality of 256-slice coronary CT angiography(CCTA)in elderly patients with free breathing and breath holding.Methods A total of 106 subjects who underwent CCTA in the Huadong Hospital Affiliated to Fudan University from June 2020 to December 2020 were selected,and they were randomly divided into the experimental group(n=53)and control group(n=53).The experimental group underwent CCTA under free breathing,and the control group did CCTA after breath holding.The heart rate of 75 beats/min was used as the grouping threshold,and the patients were divided into the fast heart rate group and slow heart rate group.The BMI,heart rate,average CT value and noise of all groups were compared,and the signal-to-noise ratio(SNR)and contrast noise ratio(CNR)were calculated according to the formula.Using double-blind method,the image quality was evaluated by two senior radiologists and the lesions of coronary artery branches were recorded.Results The SNR of the images of the experimental group and the control group at the aortic arch root and proximal coronary artery were(17.78±3.08),(29.89±5.68)and(18.12±3.17),(28.98±4.92),respectively;the CNR was(14.40±2.71),(24.28±4.90)and(14.47±2.88),(22.94±4.06),respectively.The difference between the two groups was not statistically significant(P>0.05).There was no statistically significant difference in the evaluation of objective image quality between the two groups(P>0.05).Conclusion During CCTA,the free breathing mode can be selected according to the cooperation of elderly subjects,which can improve the cooperation degree of the subjects without affecting the image quality.