Myocardial fiber orientation mapping using reduced encoding diffusion tensor imaging
Myocardial fiber orientation mapping using reduced encoding diffusion tensor imaging
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DOI：
10.1081/jcmr-100108588
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发表时间：
2001-01-01
影响因子：
6.4
通讯作者：
Henriquez, CS
中科院分区：
文献类型：
--
作者：
Hsu, EW;Henriquez, CS
心肌纤维结构的精确知识对于准确理解和解释心脏电和机械功能至关重要。弥散张量成像已被用于无创和定量表征心肌纤维取向。然而，由于该方法需要在多个编码方向和多个权重级别上测量扩散，因此所需的数据集大小可能会限制其获取时间效率。应用约简编码成像（REI）原理，对四种基本重建方案——直接替代锁孔法、基线校正锁孔法、广义序列重建对称编码锁孔法和非对称编码锁孔法——在切除心肌样本弥散张量纤维定向映射中的准确性进行了评价。结果表明，在编码减少约50%的情况下，所有REI方案的性能至少与由按比例减少的全k空间图像数量组成的控制实验相当。此外，尽管对称和非对称编码的RIGR方案的性能相似，但两种方法都比控制实验和直接替代锁孔技术有显著改进。这些发现证明了扩散张量成像的一般REI方法的潜力，并为涉及快速成像序列或替代k空间采样策略的改进方案铺平了道路，以实现更好的数据采集优化效率和性能。
A precise knowledge of the myocardial fiber architecture is essential to accurately understand and interpret cardiac electrical and mechanical functions. Diffusion tensor imaging has been used to noninvasively and quantitatively characterize myocardial fiber orientations. However, because the approach necessitates diffusion to be measured in multiple encoding directions and frequently at multiple weighting levels, the required data set size may present a limitation on its acquisition time efficiency. Applying the principles of reduced encoding imaging (REI), four basic reconstruction schemes, keyhole using direct substitution, keyhole with baseline correction, symmetrically encoded REI with generalized-series reconstruction (RIGR), and asymmetrically encoded RIGR, are evaluated in terms of their accuracy in diffusion tensor fiber orientation mapping of excised myocardial samples. Results show that the performances of all REI schemes, at approximately 50% reduced encoding, are at least comparable with that of a control experiment consisting of proportionally reduced number of full k-space images. Moreover, although performances of the symmetrically and asymmetrically encoded RIGR schemes are similar, both methods provide significant improvements over the control experiment and the direct-substitution keyhole technique. These findings demonstrate the potential of the general REI methodology for diffusion tensor imaging and pave the way for modified schemes involving rapid imaging sequences or alternative k-space sampling strategies to achieve even better data acquisition tune efficiency and performance.