A g‐factor metric for k‐t SENSE and k‐t PCA based parallel imaging
A g‐factor metric for k‐t SENSE and k‐t PCA based parallel imaging
复制标题
基于并行成像的 kât SENSE 和 kât PCA 的 gâfactor 度量
DOI：
10.1002/mrm.25606
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发表时间：
2015
影响因子：
3.3
通讯作者：
S. Kozerke
中科院分区：
文献类型：
--
作者：
C. Binter;R. Ramb;B. Jung;S. Kozerke
目的提出并验证用于评估信噪比和时间保真度的k - t SENSE、k - t PCA和相关k - t方法的g因子形式化。方法推导了时空频域的解析gxf因子公式，实现了在空间和频域对噪声和描述保真度的评估。通过对心脏电影数据的伪副本分析，验证了gxf因子描述，并使用示例数据来分析k - t方法在各种参数设置下的性能。结果分析gxf因子图与3倍、5倍和7倍k - t SENSE和k - t PCA的伪复制分析一致。虽然与k‐t PCA相比，k‐t SENSE在静态区域产生较低的平均gxavg值，但k‐t PCA在动态区域产生较低的gxavg值。k‐t PCA增加了欠采样因子，可以更好地保存时间转移。提出的gxf因子和时间转移形式可以评估k - t方法的噪声性能和时间描述保真度，包括k - t SENSE和k - t PCA。该框架能够对不同的k - t方法相对于逐帧并行成像重建进行定量比较。中华医学杂志，2016,25(5):562 - 571。©2015 Wiley期刊公司
PurposeTo propose and validate a g‐factor formalism for k‐t SENSE, k‐t PCA and related k‐t methods for assessing SNR and temporal fidelity.MethodsAn analytical gxf‐factor formulation in the spatiotemporal frequency domain is derived, enabling assessment of noise and depiction fidelity in both the spatial and frequency domain. Using pseudoreplica analysis of cardiac cine data the gxf‐factor description is validated and example data are used to analyze the performance of k‐t methods for various parameter settings.ResultsAnalytical gxf‐factor maps were found to agree well with pseudoreplica analysis for 3x, 5x, and 7x k‐t SENSE and k‐t PCA. While k‐t SENSE resulted in lower average gxfvalues (gxavg) in static regions when compared with k‐t PCA, k‐t PCA yielded lower gxavgvalues in dynamic regions. Temporal transfer was better preserved with k‐t PCA for increasing undersampling factors.ConclusionThe proposed gxf‐factor and temporal transfer formalism allows assessing noise performance and temporal depiction fidelity of k‐t methods including k‐t SENSE and k‐t PCA. The framework enables quantitative comparison of different k‐t methods relative to frame‐by‐frame parallel imaging reconstruction. Magn Reson Med 75:562–571, 2016. © 2015 Wiley Periodicals, Inc.