Pfeil Alexander, Thodberg Hans Henrik, Renz Diane M, Reinhardt Lisa, Oelzner Peter, Wolf Gunter, Böttcher Joachim
Department of Internal Medicine III, Jena University Hospital - Friedrich Schiller University Jena, Erlanger Allee 101, 07747, Jena, Germany.
Visiana, Søllerødvej 57 C, DK-2840, Holte, Denmark.
BMC Musculoskelet Disord. 2017 Jan 6;18(1):6. doi: 10.1186/s12891-016-1348-5.
The Digital X-ray Radiogrammetry (DXR) method measures the cortical bone thickness in the shafts of the metacarpals and has demonstrated its relevance in the assessment of hand bone loss caused by rheumatoid arthritis (RA). The aim of this study was to validate a novel approach of the DXR method in comparison with the original version considering patients with RA.
The study includes 49 patients with verified RA. The new version is an extension of the BoneXpert method commonly used in pediatrics which has these characteristics: (1) It introduces a new technique to analyze the images which automatically validates the results for most images, and (2) it defines the measurement region relative to the ends of the metacarpals. The BoneXpert method measures the Metacarpal Index (MCI) at the metacarpal bone (II to IV). Additionally, the MCI is quantified by the DXR X-posure System.
The new version correctly analyzed all 49 images, and 45 were automatically validated. The standard deviation between the MCI results of the two versions was 2.9% of the mean MCI. The average Larsen score was 2.6 with a standard deviation of 1.3. The correlation of MCI to Larsen score was -0.81 in both versions, and there was no significant difference in their ability to detect erosions.
The new DXR version (BoneXpert) validated 92% of the cases automatically, while the same good correlation to RA severity could be presented compared to the old version.
数字X线摄影测量法（DXR）可测量掌骨干的皮质骨厚度，并已证明其在评估类风湿关节炎（RA）所致手部骨质流失方面的相关性。本研究的目的是与原始版本相比，验证DXR方法在RA患者中的一种新方法。
该研究纳入了49例确诊为RA的患者。新版本是儿科常用的BoneXpert方法的扩展，具有以下特点：（1）它引入了一种分析图像的新技术，可自动验证大多数图像的结果；（2）它相对于掌骨末端定义测量区域。BoneXpert方法测量掌骨（II至IV）的掌骨指数（MCI）。此外，MCI通过DXR X-posure系统进行量化。
新版本正确分析了所有49幅图像，其中45幅自动验证通过。两个版本的MCI结果之间的标准差为平均MCI的2.9%。平均Larsen评分为2.6，标准差为1.3。两个版本中MCI与Larsen评分的相关性均为-0.81，它们在检测侵蚀的能力上无显著差异。
新的DXR版本（BoneXpert）自动验证了92%的病例，同时与旧版本相比，与RA严重程度具有同样良好的相关性。
