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椎间盘弹性成像用于关联剪切模块和舒缓度在压缩和曲中的舒缓度
Zachary R Davis1, Paull C Gossett1, Robert L Wilson2
1Weldon School of Biomedical Engineering, Purdue University, West Lafayette, IN, USA.
bioRxiv : the preprint server for biology
|September 21, 2023
概括
这项研究探讨了基于MRI的方法来评估椎间盘退化. 研究结果表明,应变成像和放松计可以作为磁盘健康和功能的生物标志物.
科学领域:
- 生物医学工程 生物医学工程
- 放射学 放射学是一门学科.
- 整形外科 整形外科 整形外科
背景情况:
- 椎间盘退化是腰部疼痛的主要原因,涉及组织结构和机械衰退.
- 目前的盘退化的评估方法缺乏理想的功能指标,例如机械参数,如应变和刚性.
- 磁共振放松计 (T1和T2) 对磁盘张力和硬度的预测能力在很大程度上是未知的.
研究的目的:
- 使用位移编码的MRI量化T1和T2放松时间和平面内应变.
- 估计剪切模量并将其与压缩和曲下的放松时间和应变进行比较.
- 研究基于MRI的弹性学和放松计作为磁盘退化生物标志物的潜力.
主要方法:
- 用移位编码的MRI测量T1和T2放松时间和椎间盘内平面应变.
- 在成像过程中,对磁盘施加了生理压缩和曲负荷.
- 剪切模量以直角平面估计,并与MRI放松时间和应变测量相关联.
主要成果:
- 内组织应变因负载模式 (压缩与曲) 而有所不同.
- 脉核的剪切模量明显低于纤维环,除了曲时,硬度取决于负载.
- 从压缩和曲估计的剪切模块之间的相关性很差,突出显示了未来模型中需要多模式负载的需要.
结论:
- 应变成像和基于应变的材料性质估计可以作为成像生物标志物,以区分健康的与退化的磁盘.
- 基于图像的弹性学和放松计为纵向退行性研究提供盘结构和功能的补充评估.
- 未来的磁盘机械反向模型应该整合来自多重负载条件的数据,以提高准确性.
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