Functional MRI can detect changes in intratissue strains in a full thickness and critical sized ovine cartilage defect model.
Functional MRI can detect changes in intratissue strains in a full thickness and critical sized ovine cartilage defect model.
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DOI：
10.1016/j.jbiomech.2017.10.031
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发表时间：
2018-01-03
影响因子：
2.4
通讯作者：
Neu CP
中科院分区：
文献类型：
--
作者：
Chan DD;Cai L;Butz KD;Nauman EA;Dickerson DA;Jonkers I;Neu CP
组织生物力学的功能成像可以揭示与疾病或修复相关的局部软化和硬化的细微变化，但在定义明确的动物模型中获取组织内测量的非侵入性和非破坏性方法在很大程度上缺乏。我们利用位移编码的MRI来测量在绵羊（绵羊）膝关节内侧股骨髁中创建临界尺寸缺损后软骨变形的变化，这是一种常见的原位和大型组织损伤和修复动物模型。我们通过测量组织内变形的空间图，优先考虑局部、特定部位的变化以及缺陷放置后位移和应变的变化。开发了定制数据平滑算法，以最大限度地减少采集的MRI相位数据中的噪声向计算的位移或应变的传播，并改善高纵横比组织区域中的应变测量。股骨（而非胫骨）软骨的应变幅度在承重和接触区域显著增加，尤其是在缺损位置附近，第一和第二主应变以及剪切应变分别平均增加6.7% ± 6.3%、13.4% ± 10.0%和10.0% ± 4.9%。应变异质性反映了关节内原位力学环境的复杂性，多个组织接触定义了变形行为。本研究证明了位移编码MRI在临床相关的大型动物缺损模型中检测软骨结构破坏后增加的变形模式和应变的实用性。它还定义了基于生物力学测量的成像生物标志物，特别是剪切应变，这些生物标志物对评估损伤和修复可能最敏感，并且在未来的研究中可能会进一步转化为人类。
Functional imaging of tissue biomechanics can reveal subtle changes in local softening and stiffening associated with disease or repair, but noninvasive and nondestructive methods to acquire intratissue measures in well-defined animal models are largely lacking. We utilized displacement encoded MRI to measure changes in cartilage deformation following creation of a critical-sized defect in the medial femoral condyle of ovine (sheep) knees, a common in situ and large animal model of tissue damage and repair. We prioritized visualization of local, site-specific variation and changes in displacements and strains following defect placement by measuring spatial maps of intratissue deformation. Custom data smoothing algorithms were developed to minimize propagation of noise in the acquired MRI phase data toward calculated displacement or strain, and to improve strain measures in high aspect ratio tissue regions. Strain magnitudes in the femoral, but not tibial, cartilage dramatically increased in load-bearing and contact regions especially near the defect locations, with an average 6.7% ± 6.3%, 13.4% ± 10.0%, and 10.0% ± 4.9% increase in first and second principal strains, and shear strain, respectively. Strain heterogeneity reflected the complexity of the in situ mechanical environment within the joint, with multiple tissue contacts defining the deformation behavior. This study demonstrates the utility of displacement encoded MRI to detect increased deformation patterns and strain following disruption to the cartilage structure in a clinically-relevant, large animal defect model. It also defines imaging biomarkers based on biomechanical measures, in particular shear strain, that are potentially most sensitive to evaluate damage and repair, and that may additionally translate to humans in future studies.
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影响因子：
2.8
作者：
Gratz, Kenneth R.;Wong, Benjamin L.;Bae, Won C.;Sah, Robert L.
通讯作者：
Sah, Robert L.
影响因子：
7
作者：
Neu, C. P.
通讯作者：
Neu, C. P.
DOI：
10.1016/0020-7683(95)00240-5
发表时间：
1996-12-01
影响因子：
3.6
作者：
Geers, MGD;DeBorst, R;Brekelmans, WAM
通讯作者：
Brekelmans, WAM
关节软骨变形通过位移编码成像在完整的胫骨关节中确定。
影响因子：
3.3
作者：
Chan, Deva D.;Neu, Corey P.;Hu, Maury L.
通讯作者：
Hu, Maury L.
影响因子：
3.8
作者：
Kim W;Ferguson VL;Borden M;Neu CP
通讯作者：
Neu CP