In vivo structural analysis of articular cartilage using diffusion tensor magnetic resonance imaging
In vivo structural analysis of articular cartilage using diffusion tensor magnetic resonance imaging
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DOI：
10.1016/j.mri.2009.05.012
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发表时间：
2009-11-01
影响因子：
2.5
通讯作者：
Tsutsumi, Sadami
中科院分区：
文献类型：
--
作者：
Azuma, Takashi;Nakai, Ryusuke;Tsutsumi, Sadami
目的：关节软骨是一种小组织，具有三层基质结构，三层基质之间胶原纤维的取向不同。采用弥散加权二次聚焦自旋回波回波平面成像（SE-EPI）序列对关节软骨进行优化，并利用弥散张量图像对人体关节软骨的三层结构进行成像。材料与方法：成像的对象是五个切除膝关节周围肌肉后的猪股骨头标本，五个有肉的猪关节软骨标本和五个成年男性志愿者的膝关节软骨。根据6个方向的扩散加权图像，计算平均扩散系数（MD）和各向异性分数（FA）值。估算了不同条件下试样（五个实例中的每一个）的MD和FA值。尽管关节软骨是一个小组织，但使用GRAPPA进行SE-EPI序列可以获得关节软骨中各层的基质结构。猪关节软骨在关节液和生理盐水中的MD和FA值不同。在人体关节软骨中，膝关节上的体重负荷对关节软骨表层的FA值有一定的影响。结论：该方法可用于关节软骨结构的成像，不仅在体外，而且在体内。因此，这种方法应支持阐明在体膝关节的结构和功能，并可能应用于临床实践。(C)2009 Elsevier Inc. All rights reserved.
Purpose: The articular cartilage is a small tissue with a matrix structure of three layers between which the orientation of collagen fiber differs. A diffusion-weighted twice-refocused spin-echo echo-planar imaging (SE-EPI) sequence was optimized for the articular cartilage, and the structure of the three layers of human articular cartilage was imaged in vivo from diffusion tensor images.Materials and Methods: The subjects imaged were five specimens of swine femur head after removal of the flesh around the knee joint, five specimens of swine articular cartilage with flesh present and the knee cartilage of five adult male volunteers. Based on diffusion-weighted images in six directions, the mean diffusivity (MD) and the fractional anisotropy (FA) values were calculated.Results: Diffusion tensor images of the articular cartilage were obtained by sequence optimization. The MD and FA value of the specimens (each of five examples) under different conditions were estimated. Although the articular cartilage is a small tissue, the matrix structure of each layer in the articular cartilage was obtained by SE-EPI sequence with GRAPPA. The MD and FA values of swine articular cartilage are different between the synovial fluid and saline. In human articular cartilage, the load of the body weight on the knee had an effect on the FA value of the surface layer of the articular cartilage.Conclusion: This method can be used to create images of the articular cartilage structure, not only in vitro but also in vivo. Therefore, it is suggested that this method should support the elucidation of the in vivo structure and function of the knee joint and might be applied to clinical practice. (C) 2009 Elsevier Inc. All rights reserved.