Noncontrast 3D steady-state free-precession magnetic resonance angiography of the whole chest using nonselective radiofrequency excitation over a large field of view: Comparison with single-phase 3D contrast-enhanced magnetic resonance angiography
Noncontrast 3D steady-state free-precession magnetic resonance angiography of the whole chest using nonselective radiofrequency excitation over a large field of view: Comparison with single-phase 3D contrast-enhanced magnetic resonance angiography
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DOI：
10.1097/rli.0b013e3181690179
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发表时间：
2008-06-01
影响因子：
6.7
通讯作者：
Ruehm, Stefan G.
中科院分区：
文献类型：
--
作者：
Krishnam, Mayil S.;Tomasian, Anderanik;Ruehm, Stefan G.
目的：目的：探讨非选择性射频激发三维稳态自由旋进（SSFP）磁共振血管成像（MRA）对心脏形态、胸主动脉、主肺动脉和近端冠状动脉进行评估的可行性。（男19人;女11人;年龄范围，20-74）的各种心脏和胸部血管疾病患者进行了自由呼吸呼吸导航仪门控心电图触发的非对比SSFP MRA和常规高分辨率3D对比增强MRA（CE-1.5T下胸部MRA。两名阅片人评价了两个数据集的结果、血管描绘和清晰度（从0，不可见到3，清晰度极佳）、伪影、信噪比（SNR）和14个血管节段（包括主动脉、主动脉上、肺动脉和冠状动脉）以及心腔中的对比度噪声比（CNR）。结果：3D SSFP和CE-MRA均成功完成，血管勾画采用Wilcoxon检验，观察者间变异系数采用[kappa]系数。SSFP MRA的扫描时间范围为5 - 10分钟（平均值+/-标准差，7 +/- 2分钟）。在SSFP MRA上，阅片者1和阅片者2对233（97.1%）和234（97.5%）个冠状动脉节段和心腔进行了分级，对275（91.7%）和278（92.7%）个非冠状动脉节段进行了诊断定义（2级和3级）（kappa = 0.86）。在常规CE-MRA上，阅片者1和2对10（4.2%）和12（5%）个冠状动脉节段和心腔进行了分级，对272（90.7%）和270（90%）个非冠状动脉节段进行了诊断定义（2级和3级）（kappa = 0.89）。在SSFP MRA上，每个阅片者的主动脉根、肺动脉干、近端冠状动脉和心腔的节段可见性较高（P <0.001），而主动脉上的节段可见性较低（P < 0.001）。SSFP MRA主动脉根部和主动脉的SNR和CNR值均较高（P < 0.001）。SSFP和CE-MRA上其他血管段和心腔的SNR和CNR值差异无显著性（均P > 0.05）。2名阅片者分别在7个和35个节段上显示了血管狭窄和扩张/动脉瘤。结论：非选择性射频激发的非对比3D SSFP MRA图像质量高，信噪比和CNR充足，可用于心脏和胸部血管疾病（包括先天性心脏病）的可靠评估。我们的研究结果表明，非对比SSFP MRA在显示心腔、近端冠状动脉、肺动脉干和主动脉根部方面优于CE-MRA。
Objectives: To evaluate the feasibility of three-dimensional (3D) steady-state free-precession (SSFP) magnetic resonance angiography (MRA) using nonselective radiofrequency excitation in the assessment of cardiac morphology, thoracic aorta, main pulmonary, and proximal coronary arteries.Material and Methods: Thirty consecutive patients (19 males; 11 females; age range, 20-74) with various cardiac and thoracic vascular diseases underwent free-breathing respiratory navigator-gated electrocardiogram-triggered noncontrast SSFP MRA and conventional high-resolution 3D contrast-enhanced MRA (CE-MRA) of the thorax at 1.5 T. Two readers evaluated both datasets for findings, vascular delineation and sharpness (from 0, not visualized to 3, excellent definition), artifacts, signal-to-noise ratio (SNR), and contrast-to-noise ratio (CNR) in 14 vascular segments including aorta, supra-aortic, pulmonary, and coronary arteries, and in cardiac chambers. Statistical analysis was performed using Wilcoxon test for vessel delineation, and [kappa] coefficient for interobserver variability.Results: 3D SSFP and CE-MRA were successfully performed in all patients. Scan time for SSFP MRA ranged from 5 to 10 minutes (mean +/- standard deviation, 7 +/- 2 minutes). On SSFP MRA, readers 1 and 2 graded 233 (97.1%) and 234 (97.5%) coronary arterial segments and cardiac chambers, and 275 (91.7%) and 278 (92.7%) noncoronary arterial segments with diagnostic definition (grades 2 and 3) (kappa = 0.86). On conventional CE-MRA, readers 1 and 2 graded 10 (4.2%) and 12 (5%) coronary arterial segments and cardiac chambers, and 272 (90.7%) and 270 (90%) noncoronary arterial segments with diagnostic definition (grades 2 and 3) (kappa = 0.89). Segmental visibility was higher for aortic root, pulmonary trunk, proximal coronary arteries, and heart chambers (P < 0.001), and lower for supra-aortic arteries (P < 0.001) on SSFP MRA for each reader. SNR and CNR values were higher for aortic root and aorta on SSFP MRA (P < 0.001 for both). No significant difference existed between SNR and CNR values for the other vascular segments and cardiac chambers on SSFP and CE-MRA (P > 0.05 for all). The 2 readers demonstrated vascular stenosis and dilatation/aneurysm in 7 and 35 segments on both datasets, respectively.Conclusion: Noncontrast 3D SSFP MRA with nonselective radiofrequency excitation provides high image quality and sufficient SNR and CNR for confident assessment of cardiac and thoracic vascular diseases including congenital heart diseases. Our results suggest that noncontrast SSFP MRA outperforms CE-MRA in visualization of cardiac chambers, proximal coronary arteries, pulmonary trunk, and aortic root.