Biomechanical properties and vascularity of an anterior cruciate ligament graft can be predicted by contrast-enhanced magnetic resonance imaging -: A two-year study in sheep
Biomechanical properties and vascularity of an anterior cruciate ligament graft can be predicted by contrast-enhanced magnetic resonance imaging -: A two-year study in sheep
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DOI：
10.1177/03635465010290061401
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发表时间：
2001-11-01
影响因子：
4.8
通讯作者：
S端dkamp, NP
中科院分区：
文献类型：
--
作者：
Weiler, A;Peters, G;S端dkamp, NP
磁共振成像已被用于确定移植物的完整性，并从形态上研究前交叉韧带移植物的重塑过程。本研究的目的是在长期动物模型中比较移植物的信号强度和磁共振成像的形态特征与生物力学和组织学参数。30只绵羊采用自体跟腱断裂移植物重建前交叉韧带，分别于术后6、12、24、52或104周处死动物。处死前，所有动物均行膝关节平扫和增强扫描(1.5T，质子密度加权，2 mm切片)。计算信号/噪声商数，并将数据与移植物的最大失效载荷、抗拉强度和硬度进行关联。通过内皮细胞(因子VIII)染色，用免疫组织化学方法检测移植物的血管密度。我们发现，磁共振成像上的高信号强度反映了移植物在早期重塑过程中机械性能的下降。相关分析表明，信号/噪声商与失效载荷、刚度和抗拉强度之间存在显著的线性负相关。总的来说，信号强度的对比度增强测量的相关性比平扫磁共振成像的相关性更强。免疫组织化学证实造影剂增强反映了移植组织在重塑过程中的血管状态。我们的结论是，定量测定的磁共振成像信号强度可能是以非侵入性方式跟踪移植物重塑过程的有用工具。
Magnetic resonance imaging has been used to determine graft integrity and study the remodeling process of anterior cruciate ligament grafts morphologically in humans. The goal of the present study was to compare graft signal intensity and morphologic characteristics on magnetic resonance imaging with biomechanical and histologic parameters in a long-term animal model. Thirty sheep underwent anterior cruciate ligament reconstruction with an autologous Achilles tendon split graft and were sacrificed after 6, 12, 24, 52, or 104 weeks. Before sacrifice, all animals underwent plain and contrast-enhanced (gadolinium-diethylenetriamine pentacetic acid) magnetic resonance imaging (1.5 T, proton density weighted, 2-mm sections) of their operated knees. The signal/noise quotient was calculated and data were correlated to the maximum load to failure, tensile strength, and stiffness of the grafts. The vascularity of the grafts was determined immunohistochemically by staining for endothelial cells (factor VIII). We found that high signal intensity on magnetic resonance imaging reflects a decrease of mechanical properties of the graft during early remodeling. Correlation analyses revealed significant negative linear correlations between the signal/noise quotient and the load to failure, stiffness, and tensile strength. In general, correlations for contrast-enhanced measurements of signal intensity were stronger than those for plain magnetic resonance imaging. Immunohistochemistry confirmed that contrast medium enhancement reflects the vascular status of the graft tissue during remodeling. We conclude that quantitatively determined magnetic resonance imaging signal intensity may be a useful tool for following the graft remodeling process in a noninvasive manner.