第二代运动校正算法对心肌桥-壁冠状动脉CT血管成像图像质量及测量可重复性的影响

Effect of second-generation motion correction algorithm on image quality and measurement reproducibility of coronary CT angiography in patients with myocardial bridge and mural coronary artery

目的:评价第二代运动校正算法对心肌桥-壁冠状动脉CT血管成像图像质量及测量可重复性的影响,并与第一代校正算法及未经校正图像相比较。方法:回顾性分析66例前降支心肌桥-壁冠状动脉CT图像。在45%及75%心动周期重建未经校正的标准图像、经第一代算法校正的图像及第二代算法校正图像。图像质量由两位观察者应用4分制评分(1分不合格,4分优秀)并比较。测量并比较心肌桥深度、长度以及壁冠状动脉管腔截面积及最小直径。结果:在45%心动周期,标准、第一代、第二代校正图像中壁冠状动脉图像质量评分分别为1.59±0.78,2.21±0.97,3.21±0.62;心肌桥图像质量评分分别为2.48±0.79,2.76±0.75,3.58±0.58。在75%心动周期,标准、第一代、第二代校正图像中壁冠状动脉图像质量评分分别为2.26±0.60,3.03±0.89,3.59±0.55;心肌桥图像质量评分分别为3.00±0.93,3.17±0.83,3.80±0.44。对于壁冠状动脉的显示第一代算法优于标准算法,而对与心肌桥两算法无统计学差异(P>0.05)。与标准算法及第一代校正算法相比,第二代算法提高了心肌桥与壁冠状动脉的图像质量,并且在45%和75%R-R间期的测量中有更窄的观察者间一致性区间。结论:与常规算法及第一代运动校正算法相比,第二代算法可提高心肌桥-壁冠状动脉CT图像质量及测量可重复性。

Objectives:To determine the effect of second-generation motion correction(MC2)on image quality and measurement reproducibility of cardiac CT images in patients with myocardial bridge and mural coronary artery(MB-MCA)compared to standard(STD)images without motion correction and with first-generation motion correction(MC1).Methods:A total of 66 patients with MB-MCA in the left anterior descending branch were analyzed retrospectively.Images were reconstructed at 45%and 75%R-R intervals using STD,MC1,and MC2 algorithms.Image quality for MB-MCA was assessed by two observers using a four-point scale(1=poor and 4=excellent)and compared among STD,MC1,and MC2.Depth and length of MB,lumen area and minimal diameter of MCA were measured and compared.Results:At 45%R-R interval,image quality scores were 1.59±0.78,2.21±0.97,and 3.21±0.62 for MCA,and 2.48±0.79,2.76±0.75,and 3.58±0.58 for MB with STD,MC1 and MC2,respectively.At 75%R-R interval,these values were 2.26±0.60,3.03±0.89,and 3.59±0.55 for MCA and 3.00±0.93,3.17±0.83,and 3.80±0.44 for MB.Although MC1 was superior to STD in displaying MCA,there was no statistical difference between the two algorithms for MB(P>0.05).Compared with STD and MC1,MC2 statistically improved image quality for both MCA and MB and had narrower limits in interobserver agreement for measurements at both 45%and 75%R-R intervals.Conclusion:MC2 improves CT image quality and measurement reproducibility in patients with MB-MCA compared to STD and MC1.