Department of Radiology, Okayama University Medical School, 2-5-1 Shikatacho, Kitaku, Okayama, 700-8558, Japan.
Intelligent Orthopaedic System Development, Okayama University Medical School, 2-5-1 Shikatacho, Kitaku, Okayama, 700-8558, Japan.
Eur Radiol Exp. 2020 Jan 28;4(1):4. doi: 10.1186/s41747-019-0135-0.
To reveal trends in bone microarchitectural parameters with increasing spatial resolution on ultra-high-resolution computed tomography (UHRCT) in vivo and to compare its performance with that of conventional-resolution CT (CRCT) and micro-CT ex vivo.
We retrospectively assessed 5 tiger vertebrae ex vivo and 16 human tibiae in vivo. Seven-pattern and four-pattern resolution imaging were performed on tiger vertebra using CRCT, UHRCT, and micro-CT, and on human tibiae using UHRCT. We measured six microarchitectural parameters: volumetric bone mineral density (vBMD), trabecular bone volume fraction (bone volume/total volume, BV/TV), trabecular thickness (Tb.Th), trabecular number (Tb.N), trabecular separation (Tb.Sp), and connectivity density (ConnD). Comparisons between different imaging resolutions were performed using Tukey or Dunnett T3 test.
The vBMD, BV/TV, Tb.N, and ConnD parameters showed an increasing trend, while Tb.Sp showed a decreasing trend both ex vivo and in vivo. Ex vivo, UHRCT at the two highest resolutions (1024- and 2048-matrix imaging with 0.25-mm slice thickness) and CRCT showed significant differences (p ≤ 0.047) in vBMD (51.4 mg/cm and 63.5 mg/cm versus 20.8 mg/cm), BV/TV (26.5% and 29.5% versus 13.8 %), Tb.N (1.3 l/mm and 1.48 l/mm versus 0.47 l/mm), and ConnD (0.52 l/mm and 0.74 l/mm versus 0.02 l/mm, respectively). In vivo, the 512- and 1024-matrix imaging with 0.25-mm slice thickness showed significant differences in Tb.N (0.38 l/mm versus 0.67 l/mm, respectively) and ConnD (0.06 l/mm versus 0.22 l/mm, respectively).
We observed characteristic trends in microarchitectural parameters and demonstrated the potential utility of applying UHRCT for microarchitectural analysis.
揭示超高分辨率计算机断层扫描（UHRCT）体内骨微观结构参数随空间分辨率增加的趋势，并比较其与常规分辨率 CT（CRCT）和微 CT 体外的性能。
我们回顾性评估了 5 只老虎的 16 个人类胫骨。使用 CRCT、UHRCT 和微 CT 对老虎的 7 种和 4 种模式分辨率成像，以及对人类胫骨的 UHRCT 进行成像。我们测量了 6 个微观结构参数：体积骨矿物质密度（vBMD）、骨小梁体积分数（骨体积/总体积，BV/TV）、骨小梁厚度（Tb.Th）、骨小梁数量（Tb.N）、骨小梁间距（Tb.Sp）和连通密度（ConnD）。使用 Tukey 或 Dunnett T3 检验比较不同成像分辨率之间的差异。
vBMD、BV/TV、Tb.N 和 ConnD 参数在体内和体外均呈增加趋势，而 Tb.Sp 呈减少趋势。在体外，UHRCT 在两个最高分辨率（1024-和 2048-矩阵成像，层厚 0.25-mm）和 CRCT 之间显示出显著差异（p≤0.047），vBMD（51.4 mg/cm 和 63.5 mg/cm 与 20.8 mg/cm）、BV/TV（26.5%和 29.5%与 13.8%）、Tb.N（1.3 l/mm 和 1.48 l/mm 与 0.47 l/mm）和 ConnD（0.52 l/mm 和 0.74 l/mm 与 0.02 l/mm）。在体内，512-和 1024-矩阵成像，层厚 0.25-mm 显示 Tb.N（0.38 l/mm 与 0.67 l/mm）和 ConnD（0.06 l/mm 与 0.22 l/mm）的显著差异。
我们观察到微观结构参数的特征趋势，并证明了应用 UHRCT 进行微观结构分析的潜力。
