三维旋转剪切波弹性成像纵向评估股外侧肌健康定量指标
本研究对10名健康志愿者的股外侧肌进行3个月纵向三维旋转剪切波弹性成像测量，评估沿及跨纤维方向的剪切波速度、分数各向异性及其随膝屈曲角度的增长系数。结果显示剪切波速度变异系数在10%以内，分数各向异性在13%以内，增长参数变异系数8.3%–18.7%，为设计纵向研究提供了参考。
要点
- 3个月内剪切波速度变异系数≤10%，分数各向异性≤13%，测量重复性良好。
- 增长系数βSWS,‖为0.010±0.001 deg⁻¹，βSWS,⊥为0.004±0.001 m/s/deg，βFA为0.0029±0.0007 deg⁻¹。
- 不同膝屈曲角度下测量稳定，可用于纵向监测肌肉病变。
关键影像表现/征象
- 沿纤维和跨纤维方向的剪切波速度在3个月内变异系数均在10%以内。
- 分数各向异性在3个月内变异系数在13%以内。
诊断标准与关键数值
- βSWS,‖为0.010±0.001 deg⁻¹，βSWS,⊥为0.004±0.001 m/s/deg，βFA为0.0029±0.0007 deg⁻¹。
- 增长参数平均变异系数：βSWS,‖为8.3%，βSWS,⊥为18.7%，βFA为14.8%。
临床应用与阅片要点
- 日常阅片或科研测量时，膝屈曲角度标准化（≤45°、45°、60°、90°、110°）有助于保证剪切波速度和分数各向异性的可重复性。
- 纵向随访中，剪切波速度变化在10%以内、分数各向异性变化在13%以内可能反映测量变异而非真实病理改变。
局限性
- 样本量仅10名健康志愿者，未纳入肌肉疾病患者。
- 随访时间仅3个月，长期稳定性未评估。
以上解读依据论文摘要（全文未开放获取或许可不允许翻译转载）。
英文原文（摘要）· 点击展开
OBJECTIVE: Ultrasonic 3D rotational shear wave elasticity imaging (3D-RSWEI) has previously been used to quantify the mechanical properties of muscle with good precision in single timepoint studies. However, to date, the longitudinal variability of these measurements has not been evaluated. Herein, we report the longitudinal measurements of muscle stiffness and anisotropy assessed using 3D-RSWEI over a 3 month period.
METHODS: 3D-RSWEI measurements were made in vivo in the healthy vastus lateralis of 10 participants. Over 3 mo, we quantified the shear wave speed (SWS) along and across the fibers, along with fractional anisotropy (FA) at multiple knee flexion angles (≤45∘,45∘,60∘,90∘ and 110∘), and growth coefficients parametrizing the dependence of SWS and fractional anisotropy on applied knee flexion (βSWS,‖,βSWS,⊥ and βFA). The coefficient of variation (CoV) of each SWEI-based metric of interest was also quantified over 3 months.
RESULTS: Throughout the duration of the study and across all participants, SWS measurements were consistent to within 10%CoV, with FA measurements consistent to within 13%. Fitting SWS growth versus knee flexion yielded a βSWS,‖ of 0.010±0.001(deg-1) and a βSWS,⊥ of 0.004±0.001(m/s/deg). Fitting FA growth with knee flexion yielded a βFA of 0.0029±0.0007(deg-1). Growth parameters had an average CoV of 8.3% for βSWS,‖,18.7% for βSWS,⊥ and 14.8% for βFA across all participants over 3 months.
CONCLUSION: The low variability of these SWEI-based metrics over 3 months in healthy volunteers provides a reference for designing longitudinal studies to evaluate their sensitivity to histopathologic changes associated with muscle disease progression.
引用
- Srinivasan S, Wightman WE, Bock KD, et al. Longitudinal Assessment of Quantitative Metrics for Skeletal Muscle Health Using 3D Rotational Shear Wave Elasticity Imaging in the Vastus Lateralis. Ultrasound Med Biol. 2026. PMID: 42140830. doi:10.1016/j.ultrasmedbio.2026.04.013
供执业医师工作参考，不替代临床判断；数值与分级以指南原文为准。