Irwan Roy, Lubbers Daniël D, van der Vleuten Pieter A, Kappert Peter, Götte Marco J W, Sijens Paul E
Department of Radiology, University Medical Center Groningen, State University Groningen, 9700 RB Groningen, The Netherlands.
Magn Reson Imaging. 2007 Jun;25(5):678-83. doi: 10.1016/j.mri.2006.10.012. Epub 2006 Nov 20.
Two parallel imaging methods used for first-pass myocardial perfusion imaging were compared in terms of signal-to-noise ratio (SNR), contrast-to-noise ratio (CNR) and image artifacts. One used adaptive Time-adaptive SENSitivity Encoding (TSENSE) and the other used GeneRalized Autocalibrating Partially Parallel Acquisition (GRAPPA), which are both applied to a gradient-echo sequence. Both methods were tested on 12 patients with coronary artery disease. The order of perfusion sequences was inverted in every other patient. Image acquisition was started during the administration of a contrast bolus followed by a 20-ml saline flush (3 ml/s), and the next perfusion was started at least 15 min thereafter using an identical bolus. An acceleration rate of 2 was used in both methods, and acquisition was performed during breath-holding. Significantly higher SNR, CNR and image quality were obtained with GRAPPA images than with TSENSE images. GRAPPA, however, did not yield a higher CNR when applied after the second bolus. GRAPPA perfusion imaging produced larger differences between subjects than did TSENSE. Compared to TSENSE, GRAPPA produced significantly better CNR on the first bolus. More consistent SNR and CNR were obtained from TSENSE images than from GRAPPA images, indicating that the diagnostic value of TSENSE may be better.
对用于首次通过心肌灌注成像的两种并行成像方法在信噪比（SNR）、对比噪声比（CNR）和图像伪影方面进行了比较。一种方法使用自适应时间自适应灵敏度编码（TSENSE），另一种方法使用广义自校准部分并行采集（GRAPPA），这两种方法均应用于梯度回波序列。两种方法都在12例冠心病患者身上进行了测试。每隔一名患者灌注序列的顺序颠倒。在注射造影剂团注后接着进行20 ml生理盐水冲洗（3 ml/s）期间开始图像采集，此后至少15分钟后使用相同的团注开始下一次灌注。两种方法均使用加速因子2，并在屏气期间进行采集。与TSENSE图像相比，GRAPPA图像获得了显著更高的SNR、CNR和图像质量。然而，GRAPPA在第二次团注后应用时并未产生更高的CNR。与TSENSE相比，GRAPPA灌注成像在不同受试者之间产生的差异更大。与TSENSE相比，GRAPPA在首次团注时产生的CNR明显更好。与GRAPPA图像相比，TSENSE图像获得的SNR和CNR更一致，表明TSENSE的诊断价值可能更好。
