Background

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.

Methods

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.

Results

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/cm³ and 63.5 mg/cm³ versus 20.8 mg/cm³), 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/mm³ and 0.74 l/mm³ versus 0.02 l/mm³, 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/mm³ versus 0.22 l/mm³, respectively).

Conclusions

We observed characteristic trends in microarchitectural parameters and demonstrated the potential utility of applying UHRCT for microarchitectural analysis.

中文翻译：

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使用超高分辨率CT对老虎椎骨和人类胫骨进行骨微结构分析。

背景

揭示在体内超高分辨率计算机断层扫描（UHRCT）上空间分辨率提高时骨微结构参数的趋势，并将其与常规分辨率CT（CRCT）和离体微CT的性能进行比较。

方法

我们回顾性评价5虎椎骨体外和16人的胫骨在体内。使用CRCT，UHRCT和micro-CT在老虎椎骨上进行七模式和四模式分辨率成像，使用UHRCT在人的胫骨上进行七模式和四模式分辨率成像。我们测量了六个微体系结构参数：骨矿物质密度（vBMD），小梁骨体积分数（骨体积/总体积，BV / TV），小梁厚度（Tb.Th），小梁数目（Tb.N），小梁分离（Tb） .Sp）和连接密度（ConnD）。使用Tukey或Dunnett T3测试进行了不同成像分辨率之间的比较。

结果

vBMD，BV / TV，Tb.N和ConnD参数呈上升趋势，而Tb.Sp呈离体趋势和体内呈下降趋势。离体，UHRCT在两个最高分辨率（用0.25毫米切片厚度1024-和2048矩阵成像）和CRCT显示显著差异（p在vBMD≤0.047）（51.4毫克/厘米³和63.5毫克/厘米³ 对20.8 mg / cm ³），BV / TV（26.5％和29.5％对13.8％），Tb.N（1.3 l / mm和1.48 l / mm对0.47 l / mm）和ConnD（0.52 l / mm ³和0.74） l / mm ³ 与0.02 l / mm ³分别）。在体内，切片厚度为0.25mm的512和1024矩阵成像显示Tb.N（分别为0.38 l / mm对0.67 l / mm）和ConnD（0.06 l / mm ³ 对0.22 l / mm ）存在显着差异。³）。

结论

我们观察了微体系结构参数的特征趋势，并证明了应用UHRCT进行微体系结构分析的潜在实用性。