背景:高保真心脏磁共振(MR)成像在先天性心脏病(CHD)和主动脉病的监测中起着关键作用。
目的:我们旨在评估自由呼吸的质量和准确性,使用对比增强的3DbSSFP作为参考,在CHD和主动脉病变的情况下,ECG门控非对比三维(3D)平衡稳态自由进动(bSSFP)。我们还使用了常规使用的非ECG门控2D单发(SSh)bSSFP序列之一作为非对比3DbSSFP的辅助手段。
方法:获得机构审查委员会批准,对图像质量和血管测量进行系统的回顾性分析。冠心病和主动脉病变患者,正在接受临床显示的对比增强3DbSSFP,作为临床质量改进计划的一部分,前瞻性地确定还接受额外的非对比3DbSSFP和2DSShbSSFP成像,旨在在可行的情况下减少对比剂的使用。两位读者,对彼此的评价视而不见,在5点Likert量表上对图像质量进行分级,并在两个3DbSSFP图像的单独会话中进行血管测量。他们还报道了2DSShbSSFP图像上各种纵隔大血管的可见性。原始协议,加权卡帕统计量,并计算类内相关系数(ICC)以评估两个读者之间的一致性和一致性。使用双侧配对t检验和Bland-Altman分析,对成人和儿科患者进行了非对比和对比增强3DbSSFP成像的比较分析。P值<0.05被认为对于所有推断测试是显著的。
结果:共有29名患者(17名男性,中位年龄20.3岁,四分位数间距(IQR)12.5,年龄范围7-39岁),包括11名18岁以下的儿科患者(6名男性,中位年龄14.5岁,IQR4.0,年龄范围7-17岁),进行回顾性分析。对于所有受试者(4.4±0.2,范围4.0-4.9vs3.7±0.4,范围3.1-4.7)和仅儿科受试者(4.3±0.3,范围4.0-4.9vs3.6±0.5,范围3.1-4.4),对比增强3DbSSFP的总体图像质量评分均显着高于非对比3DbSSFP(P<0.0001)。通过结合非对比3DbSSFP和2DbSSFP,读取器1和读取器2额定423和420血管诊断,分别,总共435个航段。所有标志显示相似的平均血管直径,在非对比和对比增强的3DbSSFPMR血管造影之间没有显着差异(r=0.99,偏差-0.31mm,95%的一致性限制-2.04mm至1.43mm)。
结论:尽管对比度增强的图像具有更好的整体图像质量,由非对比2DSShbSSFP和3DbSSFP全胸部图像组成的成像协议可提供诊断上足够的图像质量,和精确的血管测量,在患有冠心病和主动脉病变的儿童和成人中,与自由呼吸对比增强3DbSSFP相当。
BACKGROUND: High-fidelity cardiac magnetic resonance (MR) imaging plays a pivotal role in the surveillance of congenital heart disease (CHD) and aortopathy.
OBJECTIVE: We aimed to evaluate the quality and accuracy of free breathing, ECG-gated noncontrast three-dimensional (3D) balanced steady-state free precession (bSSFP) in cases of CHDs and aortopathies using contrast-enhanced 3D bSSFP as a reference. We also used one of our routinely used non-ECG-gated 2D-single-shot (SSh) bSSFP sequence as an adjunct to noncontrast 3D bSSFP.
METHODS: Institutional review board approval was obtained to perform a systematic retrospective analysis of image quality and vascular measurements. Patients with CHD and aortopathy, who were undergoing clinically indicated contrast-enhanced 3D bSSFP, were prospectively identified to also undergo additional noncontrast 3D bSSFP and 2D SSh bSSFP imaging as part of a clinical quality improvement initiative aimed at reducing the use of contrast when feasible. Two readers, blinded to each other\'s evaluations, graded image quality on a 5-point Likert scale and performed vascular measurements in separate sessions for both 3D bSSFP images. They also reported the visibility of various mediastinal great vessels on 2D SSh bSSFP images. Raw agreement, the weighted kappa statistic, and intra-class correlation coefficients (ICCs) were computed to assess the consistency and agreement between the two readers. Comparative analysis of noncontrast and contrast-enhanced 3D bSSFP imaging was performed in adult and pediatric patients using a two-sided paired t-test and Bland-Altman analysis. A P-value < 0.05 was considered significant for all inference testing.
RESULTS: A total of 29 patients (17 males, median age 20.3 years, interquartile range (IQR) 12.5, age range 7-39 years), including 11 pediatric patients under the age of 18 years (6 males, median age 14.5 years, IQR 4.0, age range 7-17 years), underwent retrospective analysis. The overall image quality score for contrast-enhanced 3D bSSFP was significantly higher (P < 0.0001) than that of noncontrast 3D bSSFP for both all subjects (4.4 ± 0.2, range 4.0-4.9 vs 3.7 ± 0.4, range 3.1-4.7) and only pediatric subjects (4.3 ± 0.3, range 4.0-4.9 vs 3.6 ± 0.5, range 3.1-4.4). By combining noncontrast 3D bSSFP and 2D bSSFP, reader 1 and reader 2 rated 423 and 420 vessels diagnostic, respectively, in a total of 435 vessel segments. All landmarks showed similar mean vessel diameters without significant differences between noncontrast and contrast-enhanced 3D bSSFP MR angiography (r = 0.99, bias -0.31 mm, 95% limits of agreement -2.04 mm to 1.43 mm).
CONCLUSIONS: Although contrast-enhanced images had better overall image quality, an imaging protocol consisting of noncontrast 2D SSh bSSFP and 3D bSSFP whole-chest images provides diagnostically adequate image quality, and accurate vascular measurements, comparable to free-breathing contrast-enhanced 3D bSSFP in both children and adults with CHD and aortopathies.