呼吸导航门控三维延迟增强MR序列在梗死心肌成像中的应用价值

Application Value of Respiratory Navigator-gated Three-dimensional Delayed-enhancement MR Sequence in Infarcted Myocardium Imaging

目的以屏气二维序列作为对照,探讨相位排序自动门控窗选择(PAWS)算法呼吸导航门控三维延迟增强(3DNAV DE)MR序列在梗死心肌成像中的应用价值及可行性。材料与方法 3只犬急性心肌梗死模型心脏DE-MRI:分别行常规2DBH及PAWS算法3DNAV DE-MR序列扫描,采用半定性及定量方法对比评价两个序列短轴位包含心肌梗死延迟强化灶的对应层面图像质量。结果 2位医师评价3DNAV序列图像质量一致性较好(Kappa=0.532,P<0.05);2位医师对于两个序列图像的相对诊断可行性评分呈显著正相关(r=0.609,P<0.05),3DNAV序列图像质量及相对诊断可信性好于2DBH序列;两个序列图像所测得梗死体积大小呈显著正相关(r=0.998,P<0.05);3DNAV序列图像梗死心肌信噪比SNR1(t=-5.691,P<0.01)、活性心肌SNR0(t=-3.317,P<0.01)及其梗死-活性心肌对比噪声比CNR1-0(t=-6.005,P<0.01)较2DBH序列明显提高。结论与2DBH序列相比,PAWS算法呼吸导航门控3DNAV DE-MR序列在提高成像效率的前提下,可获得更高的图像质量及心肌梗死诊断可信性。

Purpose To explore the application value and feasibility of respiratory navigator-gated three-dimensional （3DNAV） delayed-enhancement MR （DE-MR） sequence using PAWS algorithm for infarcted myocardium imaging compared with standard breath hold two-dimensional （2DBH） DE-MR sequence. Materials and Methods Three myocardium infarction dog-models underwent 2DBH and 3DNAV DE-MRI. The image quality of the two sequences were compared and evaluated by using semiqualitative and quantitative analysis. Results Good consistency （Kappa=0.532, P〈0.05） of the two radiologist＇ evaluation of 3DNAV image quality was obtained and the correlation of their relatively diagnostic reliability score was statistically significant （r=0.609, P〈0.05）. The means of relatively diagnostic reliability score of the two radiologists were both beyond 0. And infarct volume measurements obtained based on the two sequences was significantly correlated （r=0.998, P〈0.05）. Signal-to-noise ratio of infarcted myocardium （SNR1, t= -- 5.691, P〈0.01）, SNR of variable myocardium （SNRo, t-- -- 3.317, P〈0.01 ） and their contrast-to-noise ratio （CNR10. t=- -- 6.005, P〈0.01） of 3DNAV sequence markedly improved than those of 2DBH sequence and their differences were statistically significant. Conclusion PAWS algorithm 3DNAV DE-MRI of infarcted myocardium provides less scan time, higher imaging improved myocardial infarction diagnosis 2DBH DE-MRI. efficiency, improved image quality and and evaluation confidence compared with