Department of Biomedical Engineering, The Ohio State University, Columbus, Ohio, USA.
Department of Radiology, The Ohio State University Wexner Medical Center, Columbus, Ohio, USA.
J Magn Reson Imaging. 2022 Dec;56(6):1722-1732. doi: 10.1002/jmri.28151. Epub 2022 Mar 15.
Magnetic resonance elastography (MRE) is an imaging technique that can noninvasively assess the shear properties of the intervertebral disc (IVD). Unlike the standard gradient recalled echo (GRE) MRE technique, a spin-echo echo-planar imaging (SE-EPI) sequence has the potential to improve imaging efficiency and patient compliance.
To validate the use of an SE-EPI sequence for MRE of the IVD compared against the standard GRE sequence.
Cross-over.
Twenty-eight healthy volunteers (15 males and 13 females, age range: 19-55).
FIELD STRENGTH/SEQUENCE: 3 T; GRE, SE-EPI with breath holds (SE-EPI-BH) and SE-EPI with free breathing (SE-EPI-FB) MRE sequences.
MRE-derived shear stiffnesses were calculated via principal frequency analysis. SE-EPI derived shear stiffness and octahedral shear strain signal-to-noise ratios (OSS-SNR) were compared against those derived using the GRE sequence. The reproducibility and repeatability of SE-EPI stiffness measurements were determined. Shear stiffness was evaluated in the nucleus pulposus (NP) and annulus fibrosus (AF) regions of the disc. Scan times between sequences were compared.
Linear mixed models, Bland-Altman plots, and Lin's concordance correlation coefficients (CCCs) were used with P < 0.05 considered statistically significant.
Good correlation was observed between shear stiffnesses derived from the SE-EPI sequences with those derived from the GRE sequence with CCC values greater than 0.73 and 0.78 for the NP and AF regions, respectively. OSS-SNR was not significantly different between GRE and SE-EPI sequences (P > 0.05). SE-EPI sequences generated highly reproducible and repeatable stiffness measurements with CCC values greater than 0.97 in the NP and AF regions and reduced scan time by at least 51% compared to GRE. SE-EPI-BH and SE-EPI-FB stiffness measurements were similar with CCC values greater than 0.98 for both regions.
SE-EPI-based MRE-derived stiffnesses were highly reproducible and repeatable and correlated with current standard GRE MRE-derived stiffness estimates while reducing scan times.
1 TECHNICAL EFFICACY STAGE: 1.
磁共振弹性成像（MRE）是一种可以无创评估椎间盘（IVD）剪切特性的成像技术。与标准梯度回波（GRE）MRE 技术不同，自旋回波回波平面成像（SE-EPI）序列有可能提高成像效率和患者顺应性。
验证 SE-EPI 序列在评估椎间盘 MRE 方面的应用，与标准 GRE 序列进行比较。
交叉研究。
28 名健康志愿者（15 名男性和 13 名女性，年龄范围：19-55 岁）。
磁场强度/序列：3T；GRE、带屏气的 SE-EPI（SE-EPI-BH）和自由呼吸的 SE-EPI（SE-EPI-FB）MRE 序列。
通过主频率分析计算 MRE 衍生的剪切刚度。比较 SE-EPI 衍生的剪切刚度和八面体剪切应变信噪比（OSS-SNR）与 GRE 序列衍生的剪切刚度和 OSS-SNR。确定 SE-EPI 刚度测量的可重复性和再现性。评估椎间盘核和纤维环区域的剪切刚度。比较序列之间的扫描时间。
使用线性混合模型、Bland-Altman 图和 Lin 的一致性相关系数（CCC），P<0.05 被认为具有统计学意义。
SE-EPI 序列衍生的剪切刚度与 GRE 序列衍生的剪切刚度具有良好的相关性，核和纤维环区域的 CCC 值分别大于 0.73 和 0.78。OSS-SNR 在 GRE 和 SE-EPI 序列之间没有显著差异（P>0.05）。SE-EPI 序列产生了高度可重复和可再现的刚度测量值，核和纤维环区域的 CCC 值大于 0.97，与 GRE 相比扫描时间至少减少了 51%。SE-EPI-BH 和 SE-EPI-FB 刚度测量值相似，两个区域的 CCC 值均大于 0.98。
基于 SE-EPI 的 MRE 衍生的刚度具有高度的可重复性和再现性，与当前标准的 GRE MRE 衍生的刚度估计相关，同时减少了扫描时间。
1 技术功效阶段：1。
