三维快速场回波序列在先心病患儿气管支气管树MRI中的应用

The application of three-dimensional turbo field echo magnetic resonance imaging sequence in visualization of tracheobronchial tree for children with congenital heart diseases

目的对比分析三维快速场回波(3D-TFE)序列、三维平衡快速场回波(3D b-TFE)序列以及对比增强MR血管成像(CE-MRA)3种序列在显示气道时影像质量,探讨3D-TFE序列在先心病患儿气管支气管树成像中的应用价值。方法连续收集2016年9月—12月间我院62例经超声心电图确诊的先心病患儿,其中男32例,女30例,年龄2～141个月,中位年龄为12.7个月。在1.5 T MR扫描设备上进行常规心脏MRI检查,常规扫描序列3D b-TFE、CE-MRA主要显示大血管病变,3D TFE进行气管支气管成像,测量气管支气管影像信噪比(SNR)及信号强度(SI),客观评价影像质量及气管边界清晰度。由2位医生采用双盲5分法评价影像噪声及影像质量,并采用Kappa分析对2位医生的评分结果行一致性评价。采用单因素方差分析比较3种序列影像的SNR、SI、气管边界清晰度和影像质量主观评分。结果 3D-TFE序列在显示气道的SNR、SI、气管边界清晰度及其影像质量主观评分均分别高于3D b-TFE和CE-MRA序列(均P<0.05)。2位医生对3种序列影像质量的主观评分的结果一致性极好,κ值均>0.80。结论 3D-TFE序列显示气管支气管树的影像质量优于3D b-TFE和CE-MRA序列,可应用于心脏MRI检查时辅助观察有无先心病伴随的气道异常,是先心病心脏MRI检查中不可缺少的辅助序列,可为先心病患儿术前评估提供更多信息。

Objective To comparatively analyze the image quality of three-dimensional turbo field echo（3D-TFE）,three-dimensional balanced turbo field echo（3D b-TFE）, and contrast enhanced magnetic resonance angiography（CE-MRA）, and to evaluate the value of 3D-TFE in visualization of tracheobronchial tree. Methods Sixty-two consecutive children（32 boys, 30 girls; mean age： 30 months, age range： 2～141 months） were enrolled from September 2016 to December 2016, who were diagnosed congenital heart disease with echocardiography. MR was performed to provide preoperative information about anatomy or/and function. Conventional sequences（3D b-TFE and CE-MRA） were mainly used to show the extracardiac great arteries, while 3D-TFE sequence was performed to evaluate tracheobronchial anatomy. Image quality was objectively evaluated including signal-to-noise ratio（SNR）, signal intensity（SI）, and tracheal boundary clarity. Two independent observers subjectively evaluated image quality and image noise using a 5-point scale. Kappa analysis was used to evaluate the agreement between the two observers. The comparisons of SNR, SI, tracheal boundary clarity, and image quality scores were analyzed by one-way ANOVA. Results The SNR, SI, tracheal boundary clarity, and image quality scores of 3D-TFE in trachea were higher than that of 3D b-TFE and CE-MRA（both P〈0.05）. There was good inter-modality agreement between two observers for subjective image quality scores of three sequences（κ〉0.80）. Conclusion The image quality of 3D-TFE sequence for demonstrating tracheal bronchial tree is superior to the 3D b-TFE and CE-MRA sequences.As an essential auxiliary sequence for cardiac magnetic resonance imaging, 3D-TFE can detect tracheobronchial abnormalities which were associated with congenital heart diseases, and can provide helpful information for preoperative strategies.