In vitro validation of phase-contrast flow measurements at 3 T in comparison to 1.5 T:: Precision, accuracy, and signal-to-noise ratios
In vitro validation of phase-contrast flow measurements at 3 T in comparison to 1.5 T:: Precision, accuracy, and signal-to-noise ratios
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DOI：
10.1002/jmri.20275
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发表时间：
2005-05-01
影响因子：
4.4
通讯作者：
Meyer, GP
中科院分区：
文献类型：
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作者：
Lotz, J;Döker, R;Meyer, GP
目的：借助体外模型评估 3 T 相衬流测量的信噪比 (SNR)、精度和准确度，并将结果与两台 1.5-T 扫描仪的数据进行比较。材料和方法：使用相同的层流模型和序列参数设置，在一个 3-T 和两个 1.5-T 系统上进行测量。获得了 55 至 550 cm(-1) 速度编码的精度、准确度和信噪比。 SNR 是根据幅度以及流编码图像计算的。结果：所有扫描仪的体外血流模型的精密度和准确度相似，没有显着差异。对于从 55 cm(-1) 到 550 cm(-1) 的速度编码，3-T 测量的幅度和相位编码图像的 SNR 大约比从两个 1.5-T 系统获得的 SNR 高 2.5 倍。结论：即使没有针对 3-T 环境进行优化，流量测量也显示出与临床 1.5-T 扫描仪相同的高精度。 3 T 的卓越信噪比将进一步提高时间和空间分辨率。这对于冠状动脉等小型血管或缓慢的舒张血流模式很有意义。
Purpose: To evaluate the signal-to-noise ratio (SNR), precision, and accuracy of phase-contrast flow measurements at 3 T with the help of an in vitro model and to compare the results with data from two 1.5-T scanners. Materials and Methods: Using an identical setup of a laminar flow model and sequence parameters, measurements were done at one 3-T and at two 1.5-T systems. Precision, accuracy, and SNR were obtained for velocity encodings ranging from 55 up to 550 cm(-1). SNRs were calculated from the magnitude as well as the flow encoded images. Results: Precision and accuracy for the in vitro flow model were similarly high in all scanners with no significant difference. For velocity encodings from 55 cm(-1) up to 550 cm(-1), the SNR in magnitude as well as phase encoded images of the 3-T measurements was approximately 2.5 times higher than the SNR obtained from the two 1.5-T systems. Conclusion: Even without optimization for the 3-T environment, flow measurements show the same high accuracy and precision as is known from clinical 1.5-T scanners. The superior SNR at 3 T will allow further improvements in temporal and spatial resolution. This will be of interest for small-size vessels like coronary arteries or for slow diastolic flow patterns.