Quantifying vascularity in the frontoparietal dome of Stegoceras validum (Dinosauria: Pachycephalosauridae) from high resolution CT scans
Quantifying vascularity in the frontoparietal dome of Stegoceras validum (Dinosauria: Pachycephalosauridae) from high resolution CT scans
复制标题
通过高分辨率 CT 扫描量化剑角龙（恐龙：厚头龙科）额顶圆顶的血管分布
DOI：
10.1080/02724634.2021.2036991
复制
发表时间：
2022
影响因子：
1.4
通讯作者：
Evans, David C.
中科院分区：
文献类型：
--
作者：
Nirody, Jasmine A.;Goodwin, Mark B.;Horner, John R.;Huynh, Tony L.;Colbert, Matthew W.;Smith, David K.;Evans, David C.
厚头龙恐龙增厚的额顶叶在个体发育过程中从平头到圆顶状态急剧膨胀。这种扩张导致带状组织的形成，其特征主要是血管和骨组织结构的差异，通过个体发生变化。额顶叶CT扫描中发现的空洞空间是相对血管分布的合适代表。在肿头龙剑角兽中，相对血管的增加发生在穹顶的发育过程中，随后在后期个体发育中显著减少。我们采用了一种改编自人类皮质骨成像算法的脚本：(1)确定任何给定CT切片中血管的百分比；(2)量化观察到的完整额顶叶内相对血管的变化；(3)鉴定剑角龙颅骨生长系列中血管的个体发生变化。在CT扫描中识别的形态学标志有助于对颅骨间穹顶的同源区域进行准确的切片比较。这个新工具可以：(1)从CT扫描中对骨血管的完整评估；（二）适用于脊椎动物骨骼中的化石骨或现代骨；(3)提供了一种替代逐像素手动阈值的方法，这是一个耗时且主观的过程。
The thickened frontoparietal in pachycephalosaurid dinosaurs expands dramatically during ontogeny from a flat-headed to a domed state. This expansion results in the formation of zonal tissue characterized largely by differences in vascularity and bony tissue structure that changes through ontogeny. Void space identified in CT scans of the frontoparietal is a suitable proxy for relative vascularity. An increase in relative vascularity occurs with the development of the dome in the pachycephalosaurStegoceras validum, followed by a significant decrease in late stage ontogeny. We employ a script adapted from an algorithm for human cortical bone imaging to: (1) determine the percent vascularity in any given CT slice; (2) quantify these observed changes in relative vascularity within a complete frontoparietal; and (3) identify ontogenetic changes in vascularity from a cranial growth series ofStegoceras.Morphological landmarks identified in the CT scans facilitate an accurate slice-by-slice comparison of homologous regions of the dome between skulls. This new tool enables: (1) a complete assessment of bone vascularity from CT scans; (2) is applicable to any fossil or modern bone in the vertebrate skeleton; and (3) provides an alternative measure to pixel-by-pixel manual thresholding, a time intensive and subjective process.