Advanced Knee Structure Analysis (AKSA): a comparison of bone mineral density and trabecular texture measurements using computed tomography and high-resolution peripheral quantitative computed tomography of human knee cadavers
Advanced Knee Structure Analysis (AKSA): a comparison of bone mineral density and trabecular texture measurements using computed tomography and high-resolution peripheral quantitative computed tomography of human knee cadavers
复制标题
DOI：
10.1186/s13075-016-1210-z
复制
发表时间：
2017-01-10
影响因子：
4.9
通讯作者：
Engelke, Klaus
中科院分区：
文献类型：
--
作者：
Lowitz, Torsten;Museyko, Oleg;Engelke, Klaus
背景：膝关节负荷条件的改变会导致软骨下骨的改变，并可能是骨关节炎(OA)的原因之一。然而，由于成像设备的空间分辨率的限制，活体小梁结构的量化是困难的；一种方法是使用纹理参数。在以前的研究中，我们已经使用数字模型来模拟在骨性关节炎进展过程中软骨下骨结构的变化。其中一个主要结果是，利用CT图像，软骨下骨密度(BMD)结合各向异性和全局均质性可以表征这一进展。方法：研究纹理分析在临床CT检查中表征骨结构的适用性，并与HR-pQCT结果进行比较。57具人体膝关节身体(OA状态未知)接受了两种成像方式的检查。三维(3D)分割和配准过程，以及三维分析感兴趣体积(VOI)的自动定位，确保了CT和HR-pQCT数据集在相同解剖位置测量BMD和纹理参数。结果：根据骰子比率(>；0.978)的计算，不同方法之间的VOI定位精度良好。熵、各向异性和全局非均质性在两种方法之间显示出显著的线性相关性(0.68<；R-2<；1.00)。结论：基于HR-pQCT和CT的测量的高相关性、全局不均匀性和各向异性表明了不同设备之间在纹理量化方面的互换性。实验确定的整体不均匀性和各向异性的分辨率依赖关系与早期模拟的一致性是将其用于量化软骨下骨结构的一个重要里程碑。然而，仍然需要进行体内研究来确定它们的临床相关性。
Background: A change of loading conditions in the knee causes changes in the subchondral bone and may be a cause of osteoarthritis (OA). However, quantification of trabecular architecture in vivo is difficult due to the limiting spatial resolution of the imaging equipment; one approach is the use of texture parameters. In previous studies, we have used digital models to simulate changes of subchondral bone architecture under OA progression. One major result was that, using computed tomography (CT) images, subchondral bone mineral density (BMD) in combination with anisotropy and global homogeneity could characterize this progression.Method: The applicability of texture analysis to characterize bone architecture in clinical CT examinations was investigated and compared to results obtained from HR-pQCT. Fifty-seven human knee cadavers (OA status unknown) were examined with both imaging modalities. Three-dimensional (3D) segmentation and registration processes, together with automatic positioning of 3D analysis volumes of interest (VOIs), ensured the measurement of BMD and texture parameters at the same anatomical locations in CT and HR-pQCT datasets.Results: According to the calculation of dice ratios (> 0.978), the accuracy of VOI locations between methods was excellent. Entropy, anisotropy, and global inhomogeneity showed significant and high linear correlation between both methods (0.68< R-2 < 1.00). The resolution dependence of these parameters simulated earlier was confirmed by the in vitro measurements.Conclusion: The high correlation of HR-pQCT- and CT-based measurements of entropy, global inhomogeneity, and anisotropy suggests interchangeability between devices regarding the quantification of texture. The agreement of the experimentally determined resolution dependence of global inhomogeneity and anisotropy with earlier simulations is an important milestone towards their use to quantify subchondral bone structure. However, an in vivo study is still required to establish their clinical relevance.