Biomedical Physics Interdepartmental Program University of California, Los Angeles, California, USA; Department of Radiological Sciences, University of California, Los Angeles, California, USA.
J Magn Reson Imaging. 2014 Feb;39(2):463-8. doi: 10.1002/jmri.24162. Epub 2013 Apr 30.
To assess the intra- and interscan reproducibility of LV twist using FAST. Assessing the reproducibility of the measurement of new MRI biomarkers is an important part of validation. Fourier Analysis of STimulated Echoes (FAST) is a new MRI tissue tagging method that has recently been shown to compare favorably with conventional estimates of left ventricular (LV) twist from cardiac tagged images, but with significantly reduced user interaction time.
Healthy volunteers (N = 10) were scanned twice using FAST over 1 week. On day 1, two measurements of LV twist were collected for intrascan comparisons. Measurements for LV twist were again collected on day 8 for interscan assessment. LV short-axis tagged images were acquired on a 3 Tesla (T) scanner to ensure detectability of tags during early and mid-diastole. Peak LV twist is reported as mean ± SD. Reproducibility was assessed using the concordance correlation coefficient (CCC) and the repeatability coefficient (RC) (95% confidence interval [CI] range).
Mean peak twist measurements were 13.4 ± 4.3° (day 1, scan 1), 13.6 ± 3.7° (day 1, scan 2), and 13.0 ± 2.7° (day 8). Bland-Altman analysis resulted in intra- and interscan bias and 95% CI of -0.6° [-1.0°, 1.6°] and 1.4° (-1.0°, 3.0°), respectively. The Bland-Altman RC for peak LV twist was 2.6° and 4.0° for intra- and interscan, respectively. The CCC was 0.9 and 0.6 for peak LV twist for intra- and interscan, respectively.
FAST is a semi-automated method that provides a quick and quantitative assessment of LV systolic and diastolic twist that demonstrates high intrascan and moderate interscan reproducibility in preliminary studies.
使用快速心脏磁共振成像（FAST）评估左心室（LV）扭转的内扫描和间扫描可重复性。评估新的 MRI 生物标志物测量的可重复性是验证的重要组成部分。快速傅里叶分析的刺激回波（FAST）是一种新的 MRI 组织标记方法，最近已被证明与心脏标记图像的常规 LV 扭转估计相比具有优势，但用户交互时间明显减少。
健康志愿者（N=10）在一周内使用 FAST 进行了两次扫描。在第 1 天，进行了两次 LV 扭转的测量，用于内扫描比较。在第 8 天，再次采集 LV 扭转的测量值，用于间扫描评估。使用 3 特斯拉（T）扫描仪采集 LV 短轴标记图像，以确保在早期和中期舒张期能够检测到标记。报告 LV 峰值扭转作为平均值±标准差。使用一致性相关系数（CCC）和重复性系数（RC）（95%置信区间[CI]范围）评估可重复性。
平均峰值扭转测量值为 13.4°±4.3°（第 1 天，扫描 1）、13.6°±3.7°（第 1 天，扫描 2）和 13.0°±2.7°（第 8 天）。Bland-Altman 分析得出内扫描和间扫描的偏差和 95%CI 分别为-0.6°[-1.0°，1.6°]和 1.4°[-1.0°，3.0°]。峰值 LV 扭转的 Bland-Altman RC 分别为 2.6°和 4.0°，用于内扫描和间扫描。峰值 LV 扭转的 CCC 分别为 0.9 和 0.6，用于内扫描和间扫描。
FAST 是一种半自动方法，可快速定量评估 LV 收缩期和舒张期扭转，在初步研究中显示出较高的内扫描和中等的间扫描可重复性。
