QUANTITATIVE MICROTOMOGRAPHY OF BONE TRABECULAE

描述（由申请人提供）：脊柱X线计算机断层扫描， HIP是一种用于定量骨矿物质测量已建立的方法， 解析1毫米大小的元素。对于骨骼标本，高分辨率 实验室计算机断层扫描系统可以描述松质骨 具有约50微米的分辨元件的结构。这足以 描述骨体积、骨小梁厚度和方向，以及 连通性。我们最近开发了一种新的创新方法， 对单个骨小梁进行定量计算机断层扫描， 1微米的元素。 从松质骨标本中分离出整个骨小梁，并在 250微米直径的盐水填充管。同步加速器发出的x射线束 源使用波带片聚焦，并用于进行大量测量， 辐射传输然后将测量的数据重建为600 x 600 x 540值阵列，在X、Y和Z方向上的间距为1/3微米 方向本项目将使用高速扫描设备， 每天检查16个样本。 该方法对于评价显微镜下的 骨组织相对于基质矿化的性质， 与骨细胞陷窝相关的孔隙度。为了实现这一目标，四 提出了生物医学实验，遗传学，药理学， 生物力学变量将用于改变动物的骨组织。之前 经验表明，这些模型应该改变矿化， 微观尺度上的孔隙度。

DESCRIPTION (provided by applicant): X-ray computed tomography of the spine and hip is an established method for quantitative bone mineral measurement that resolves elements with 1-millimeter size. For bone specimens, high-resolution laboratory computed tomography systems can describe cancellous bone architecture with resolved elements of about 50 micrometers. This is sufficient to describe bone volume, trabecular thickness and orientation, and connectivity. We have recently developed a new innovative method to perform quantitative computed tomography on an individual bone trabecula with resolved elements of 1 micrometer. Whole trabeculae are separated from cancellous bone specimens and scanned in a 250 micrometer diameter saline filled tube. A beam of x-rays from a synchrotron source is focused using a zone plate and used to make numerous measurements of radiation transmission. The measured data is then reconstructed to a 600 x 600 x 540 array of values having a spacing of 1/3 micrometers in the X, Y, and Z direction. High speed scanning devices will be used on this project to enable examination of 16 specimens per day. This method should be extremely valuable for evaluating the microscopic properties of bone tissue with respect to the mineralization of the matrix and porosity associated with osteocyte lacunae. To establish this value, four biomedical experiments are proposed for which genetic, pharmacologic, and biomechanic variables will be used to alter the bone tissue in animals. Prior experience indicates that these models should alter the mineralization and porosity at a microscopic scale.