AUVA Trauma Center Vienna-Meidling, Department for Trauma Surgery, Vienna, Austria; Ludwig Boltzmann Institute for Experimental and Clinical Traumatology, Vienna, Austria; Austrian Cluster for Tissue Regeneration, Vienna, Austria.
Ludwig Boltzmann Institute of Osteology at Hanusch Hospital of OEGK and AUVA Trauma Center Vienna-Meidling, Vienna, Austria.
Bone. 2021 Jun;147:115915. doi: 10.1016/j.bone.2021.115915. Epub 2021 Mar 13.
Osteogenesis imperfecta (OI) is a rare genetic disorder characterized by impaired bone quality and quantity. Established imaging techniques have limited reliability in OI. The TX-Analyzer™ is a new, fractal-based software allowing a non-invasive assessment of bone structure based on conventional radiographs. We explored whether the TX-Analyzer™ can discriminate OI patients and healthy controls. Furthermore, we investigated the correlation between TX-Analyzer™ parameters and (i) bone mineral density (BMD) by Dual Energy X-ray Absorptiometry (DXA), (ii) trabecular bone score (TBS), and (iii) bone microstructure by high-resolution peripheral quantitative computed tomography (HR-pQCT).
Data of 29 adult OI patients were retrospectively analyzed. Standard radiographs of the thoracic and lumbar spine were evaluated using the TX-Analyzer™. Bone Structure Value (BSV), Bone Variance Value (BVV), and Bone Entropy Value (BEV) were measured at the vertebral bodies T7 to L5. Data were compared to a healthy, age- and gender-matched control group (n = 58). BMD by DXA, TBS, and trabecular bone microstructure by means of HR-pQCT were correlated to TX-Analyzer™ parameters in OI patients. The accuracy of the TX-Analyzer™ parameters in detecting OI was assessed with area under curve (AUC) analysis of receiver operating characteristic (ROC).
BEV of the thoracic and the lumbar spine were significantly lower in OI patients compared to controls (both p < 0.001). BEV of the thoracic spine was significantly correlated to TBS (ρ = 0.427, p = 0.042) as well as trabecular number (Tb.N) at the radius (ρ = 0.603, p = 0.029) and inhomogeneity of the trabecular network (Tb.1/N.SD) at the radius (ρ = -0.610, p = 0.027), when assessed by HR-pQCT. No correlations were found between BEV and BMD by DXA. BEV of the thoracic and the lumbar spine had an AUC of 0.81 (95% confidence interval [CI] 0.67-0.94, p < 0.001) and 0.73 (95% CI 0.56-0.89, p = 0.008), respectively. BSV and BVV did not differ between OI patients and controls.
The software TX-Analyzer™ is able to discriminate patients with OI from healthy controls. ROC curves of BEV values suggest a suitable clinical applicability. Low to no correlations with conventional methods suggest, that the TX-Analyzer™ may indicate a new and independent examination tool in OI.
成骨不全症（OI）是一种罕见的遗传性疾病，其特征是骨质量和数量受损。已有的影像学技术在评估 OI 方面的可靠性有限。TX-Analyzer™ 是一种新的基于分形的软件，可以基于常规射线照片对骨结构进行非侵入性评估。我们探讨了 TX-Analyzer™ 是否可以区分 OI 患者和健康对照者。此外，我们还研究了 TX-Analyzer™ 参数与（i）双能 X 射线吸收法（DXA）测定的骨密度（BMD）、（ii）骨小梁评分（TBS）和（iii）通过高分辨率外周定量计算机断层扫描（HR-pQCT）检测的骨微观结构之间的相关性。
回顾性分析了 29 例成年 OI 患者的数据。使用 TX-Analyzer™ 对胸腰椎的标准射线照片进行评估。在 T7 到 L5 椎体处测量骨结构值（BSV）、骨方差值（BVV）和骨熵值（BEV）。将数据与年龄和性别匹配的健康对照组（n=58）进行比较。通过 DXA 测定 BMD、TBS 以及 HR-pQCT 检测的骨小梁微观结构，与 OI 患者的 TX-Analyzer™ 参数相关联。通过接收者操作特征（ROC）曲线的曲线下面积（AUC）分析评估 TX-Analyzer™ 参数在检测 OI 中的准确性。
与对照组相比，OI 患者的胸腰椎 BEV 明显降低（均 p<0.001）。胸腰椎 BEV 与 TBS 显著相关（ρ=0.427，p=0.042），与桡骨的骨小梁数量（Tb.N）（ρ=0.603，p=0.029）和桡骨的骨小梁网络异质性（Tb.1/N.SD）（ρ=0.610，p=0.027）也显著相关，这些参数通过 HR-pQCT 进行评估。BEV 与 DXA 测定的 BMD 之间未发现相关性。胸腰椎 BEV 的 AUC 分别为 0.81（95%置信区间 [CI] 0.67-0.94，p<0.001）和 0.73（95% CI 0.56-0.89，p=0.008）。OI 患者和对照组之间的 BSV 和 BVV 没有差异。
软件 TX-Analyzer™ 能够区分 OI 患者和健康对照者。BEV 值的 ROC 曲线表明其具有良好的临床适用性。与常规方法的低相关性或无相关性表明，TX-Analyzer™ 可能是 OI 的一种新的独立检查工具。
