Inter-subject comparison of MRI knee cartilage thickness
Inter-subject comparison of MRI knee cartilage thickness
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DOI：
10.1016/j.media.2007.08.002
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发表时间：
2008-04-01
影响因子：
10.9
通讯作者：
Majumdar, Sharmila
中科院分区：
文献类型：
--
作者：
Carballido-Gamio, Julio;Bauer, Jan S.;Majumdar, Sharmila
在本文中，我们介绍了基于骨结构配准的当前图像处理技术的发展和应用，以进行膝关节软骨厚度的MRI学科间比较。骨表面的每个点都是骨-软骨界面的一部分，被赋予一个软骨厚度值。软骨和相应的骨结构被分割，它们的形状被内插以创建各向同性体素。在骨-软骨界面上计算每个点的软骨厚度并转移到骨表面。然后根据形状匹配计算骨表面对应的解剖点，使用称为形状上下文的3D形状描述符以仿射和弹性转换注册骨骼，然后执行软骨厚度值的点对点比较。一种替代技术的软骨形状插值使用变形技术也提出。基于猪膝盖图像的体积测量，使用水位移法测量软骨体积，并基于用既定技术计算的数字厚度值，视觉上验证了软骨分割和变形。使用3D形状上下文的形状匹配通过视觉验证，并与放射科医生执行的手动形状匹配进行对比。建立了受试者内部和受试者之间软骨厚度比较的可重复性，以及使用所提出的技术建立平均股骨形状、软骨厚度图和软骨覆盖图的可行性。结果表明，所提出的技术是稳健的，准确的，可重复执行点对点膝关节软骨厚度值的主体间比较。(c) 2007 Elsevier B.V.版权所有
In this paper, we present the development and application of current image processing techniques to perform MRI inter-subject comparison of knee cartilage thickness based on the registration of bone structures. Each point in the bone surface which is part of the bone-cartilage interface is assigned a cartilage thickness value. Cartilage and corresponding bone structures are segmented and their shapes interpolated to create isotropic voxels. Cartilage thicknesses are computed for each point in the bone-cartilage interfaces and transferred to the bone surfaces. Corresponding anatomic points are then computed for bone surfaces based on shape matching using 3D shape descriptors called shape contexts to register bones with affine and elastic transformations, and then perform a point to point comparison of cartilage thickness values. An alternative technique for cartilage shape interpolation using a morphing technique is also presented. The cartilage segmentation and morphing were validated visually, based on volumetric measurements of porcine knee images which cartilage volumes were measured using a water displacement method, and based on digital thickness values computed with an established technique. Shape matching using 3D shape contexts was validated visually and against manual shape matching performed by a radiologist. The reproducibility of intra- and inter-subject cartilage thickness comparisons was established, as well as the feasibility of using the proposed technique to build a mean femoral shape, cartilage thickness map, and cartilage coverage map. Results showed that the proposed technique is robust, accurate, and reproducible to perform point to point inter-subject comparison of knee cartilage thickness values. (c) 2007 Elsevier B.V. All rights reserved.