Center for Machine Vision and Signal Analysis, Faculty of Information Technology and Electrical Engineering, University of Oulu, Oulu, Finland.
Research Unit of Medical Imaging, Physics and Technology, Faculty of Medicine, University of Oulu, Oulu, Finland; Infotech Oulu, University of Oulu, Oulu, Finland.
Osteoarthritis Cartilage. 2017 Dec;25(12):2039-2046. doi: 10.1016/j.joca.2017.09.008. Epub 2017 Sep 28.
Our aim was to investigate the relation between radiograph-based subchondral bone structure and cartilage composition assessed with delayed gadolinium enhanced magnetic resonance imaging of cartilage (dGEMRIC) and T relaxation time.
Ninety-three postmenopausal women (Kellgren-Lawrence grade 0: n = 13, 1: n = 26, 2: n = 54) were included. Radiograph-based bone structure was assessed using entropy of the Laplacian-based image (E) and local binary patterns (E), homogeneity indices of the local angles (HI, HI, HI), and horizontal (FD) and vertical fractal dimensions (FD). Mean dGEMRIC index and T relaxation time of tibial cartilage were calculated to estimate cartilage composition.
HI (r = -0.22) and HI (r = -0.24) in medial subchondral bone were related (P < 0.05) to dGEMRIC index of the medial tibial cartilage. E (r = -0.23), FD (r = 0.21) and FD (r = 0.24) in medial subchondral bone were related (P < 0.05) to T relaxation time values of the medial tibial cartilage. FD at different scales in lateral subchondral bone were related (P < 0.01) to dGEMRIC index (r = 0.29-0.41) and T values of lateral tibial cartilage (r = -0.28 to -0.36). FD at larger scales were related (P < 0.05) to dGEMRIC index (r = 0.24-0.25) and T values of lateral tibial cartilage (r = -0.21). HI (r = -0.25) and FD (r = 0.22) in the lateral tibial trabecular bone were related (P < 0.05) to dGEMRIC index of the lateral tibial cartilage.
Our results support the presumption that several tissues are affected in the early osteoarthritis (OA). Furthermore, they indicate that the detailed analysis of radiographs may serve as a complementary imaging tool for OA studies.
我们旨在探究通过基于拉普拉斯图像熵（E）和局部二值模式（E）、局部角度均匀度指数（HI、HI、HI）以及水平（FD）和垂直分形维数（FD）评估的基于 X 线的软骨下骨结构与通过延迟钆增强磁共振成像软骨（dGEMRIC）和 T 弛豫时间评估的软骨成分之间的关系。
共纳入 93 名绝经后女性（Kellgren-Lawrence 分级 0：n=13，1：n=26，2：n=54）。使用基于拉普拉斯的图像熵（E）和局部二值模式（E）、局部角度均匀度指数（HI、HI、HI）以及水平（FD）和垂直分形维数（FD）评估基于 X 线的骨结构。计算胫骨软骨的平均 dGEMRIC 指数和 T 弛豫时间，以评估软骨成分。
内侧软骨下骨的 HI（r=-0.22）和 HI（r=-0.24）与内侧胫骨软骨的 dGEMRIC 指数相关（P<0.05）。内侧软骨下骨的 E（r=-0.23）、FD（r=0.21）和 FD（r=0.24）与内侧胫骨软骨的 T 弛豫时间值相关（P<0.05）。外侧软骨下骨不同尺度的 FD 与外侧胫骨软骨的 dGEMRIC 指数（r=0.29-0.41）和 T 值（r=-0.28 至-0.36）相关（P<0.01）。较大尺度的 FD 与外侧胫骨软骨的 dGEMRIC 指数（r=0.24-0.25）和 T 值（r=-0.21）相关（P<0.05）。外侧胫骨小梁骨的 HI（r=-0.25）和 FD（r=0.22）与外侧胫骨软骨的 dGEMRIC 指数相关（P<0.05）。
我们的研究结果支持这样一种假设，即几种组织在早期骨关节炎（OA）中受到影响。此外，它们表明，对 X 线片的详细分析可能成为 OA 研究的一种补充成像工具。
