Cardiac SSFP imaging at 3 tesla
Cardiac SSFP imaging at 3 tesla
复制标题
DOI：
10.1002/mrm.20024
复制
发表时间：
2004-04-01
影响因子：
3.3
通讯作者：
Boesiger, P
中科院分区：
文献类型：
--
作者：
Schär, M;Kozerke, S;Boesiger, P
平衡稳态自由进动（SSFP）技术在高信噪比（SNR）下提供心肌和血液之间的出色对比。因此，SSFP成像已成为在1.5T下评估心脏功能的首选方法。在更高场强下SNR的预期改善促使我们在3.0T下实现SSFP。在这项工作中，一个优化的序列协议，在3.0T的心脏SSFP成像的推导，考虑到在较高的字段，如均匀性，较长的T-1，和功率沉积限制增加字段的几个部分不利影响。SSFP对比度是通过优化最短TR的射频（RF）场强的最大幅度，以及通过局部线性或二阶匀场和局部优化谐振频率来建立的。考虑到增加的SNR，可以采用灵敏度编码（SENSE）来缩短屏气时间。短轴，长轴，和四腔电影在健康成人受试者获得的意见，并讨论了三种不同类型的文物沿着与潜在的方法，以减少他们。(C)2004 Wiley-Liss，Inc.
Balanced steady-state free precession (SSFP) techniques provide excellent contrast between myocardium and blood at a high signal-to-noise ratio (SNR). Hence, SSFP imaging has become the method of choice for assessing cardiac function at 1.5T. The expected improvement in SNR at higher field strength prompted us to implement SSFP at 3.0T. In this work, an optimized sequence protocol for cardiac SSFP imaging at 3.0T is derived, taking into account several partly adverse effects at higher field, such as increased field in homogeneities, longer T-1, and power deposition limitations. SSFP contrast is established by optimizing the maximum amplitude of the radiofrequency (RF) field strength for shortest TR, as well as by localized linear or second-order shimming and local optimization of the resonance frequency. Given the increased SNR, sensitivity encoding (SENSE) can be employed to shorten breath-hold times. Short-axis, long-axis, and four-chamber cine views obtained in healthy adult subjects are presented, and three different types of artifacts are discussed along with potential methods for reducing them. (C) 2004 Wiley-Liss, Inc.