Favre Julien, Babel Hugo, Cavinato Alessandro, Blazek Katerina, Jolles Brigitte M, Andriacchi Thomas P
Swiss BioMotion Lab, Department of Musculoskeletal Medicine, Lausanne University Hospital and University of Lausanne (CHUV-UNIL), CH-1011 Lausanne, Switzerland.
Department of Mechanical Engineering, Stanford University, Stanford, CA 94305, USA.
J Clin Med. 2021 Jan 26;10(3):461. doi: 10.3390/jcm10030461.
Alterations in cartilage thickness (CTh) are a hallmark of knee osteoarthritis, which remain difficult to characterize at high resolution, even with modern magnetic resonance imaging (MRI), due to a paucity of standardization tools. This study aimed to assess a computational anatomy method producing standardized two-dimensional femorotibial CTh maps. The method was assessed with twenty knees, processed following three common experimental scenarios. Cartilage thickness maps were obtained for the femorotibial cartilages by reconstructing bone and cartilage mesh models in tree-dimension, calculating three-dimensional CTh maps, and anatomically standardizing the maps. The intra-operator accuracy (median (interquartile range, IQR) of -0.006 (0.045) mm), precision (0.152 (0.070) mm), entropy (7.02 (0.71) and agreement (0.975 (0.020))) results suggested that the method is adequate to capture the spatial variations in CTh and compare knees at varying osteoarthritis stages. The lower inter-operator precision (0.496 (0.132) mm) and agreement (0.808 (0.108)) indicate a possible loss of sensitivity to detect differences in a setting with multiple operators. The results confirmed the promising potential of anatomically standardized maps, with the lower inter-operator reproducibility stressing the need to coordinate operators. This study also provided essential reference data and indications for future research using CTh maps.
软骨厚度（CTh）的改变是膝关节骨关节炎的一个标志，由于缺乏标准化工具，即使使用现代磁共振成像（MRI），在高分辨率下也难以对其进行特征描述。本研究旨在评估一种生成标准化二维股骨胫骨CTh图谱的计算解剖学方法。该方法在二十个膝关节上进行了评估，并按照三种常见的实验场景进行处理。通过重建三维骨骼和软骨网格模型、计算三维CTh图谱以及对图谱进行解剖学标准化，获得了股骨胫骨软骨的厚度图谱。操作者内准确性（中位数（四分位间距，IQR）为-0.006（0.045）mm）、精密度（0.152（0.070）mm）、熵（7.02（0.71））和一致性（0.975（0.020））结果表明，该方法足以捕捉CTh的空间变化，并比较不同骨关节炎阶段的膝关节。操作者间较低的精密度（0.496（0.132）mm）和一致性（0.808（0.108））表明，在有多个操作者的情况下，检测差异的敏感性可能会降低。结果证实了解剖学标准化图谱具有广阔的应用前景，而操作者间较低的可重复性强调了协调操作者的必要性。本研究还为未来使用CTh图谱的研究提供了重要的参考数据和指导。
