SUB-MICRON X-RAY TOMOGRAPHY OF CALCIFIED TISSUE

钙化组织的亚微米 X 射线断层扫描

• 批准号: 6056752
• 负责人: Michael J Flynn
• 金额: $ 10.06万
• 依托单位: HENRY FORD HEALTH SYSTEM
• 依托单位国家: 美国
• 财政年份: 1998
• 资助国家: 美国
• 起止时间: 1998-09-01 至 2001-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6056752
• 关键词: X ray; bioengineering /biomedical engineering; bioimaging /biomedical imaging; biomedical equipment development; bone imaging /visualization /scanning; calcification; charge coupled device camera; clinical biomedical equipment; computer data analysis; digital imaging; human tissue; image enhancement; image processing; method development; particle accelerators; radiation detector; scintillation cameras; tomography

DESCRIPTION (Adapted from the applicant's abstract): Calcium precipitates in human tissue as a part of the formation of bone, teeth, or in certain abnormal processes (i.e., such as benign or malignant calcifications of the breast, vascular plaque, stones formed in the kidney or gallbladder, etc.). In bone, tissue is formed with a complex hierarchical structure which produces oriented material properties. Conventional microscopy methods are not suitable for studying this three dimensional (3-D) structure since both light and energetic electrons have minimal penetration into mineralized tissue. X-rays in the energy range from 7 to 11 keV penetrate small calcified tissue specimens of 50 to 250 micrometer dimension with characteristics that may permit measurement of the 3-D distribution of mineral concentration with a resolution of 0.1 to 0.5 micrometer. 3D X-ray microtomography is a method wherein many radiographic views of a specimen are acquired from different direction and the data reconstructed with a computer to produce an array (512 x 512 x 256) of values proportional to the X-ray attenuation coefficient of the specimen at many locations. Methods using microfocus X-ray tubes have been frequently used to study bone specimens with a size ranging from 4 to 20 mm with a resolution of 25 to 125 microns. Microtomography using synchrotron X-ray sources is capable of better resolution but detector limitations have limited present methods to a resolution of 2 to 25 micrometers. The applicant proposes to investigate a method using X-rays from a synchrotron source (the Advanced Photon Source, APS, at Argonne National Laboratory) which might achieve a resolution of 0.1 to 0.5 micrometer. An innovative approach using a zone plate to focus an X-ray beam to a sub-micron spot is proposed. The approach combines methods developed for scanning X-ray microscopy using lower X-ray energies and methods for tomographic reconstruction developed for cone beam tomography using electron beam X-ray sources. The methods developed will be evaluated using wet bone specimens. The ability to determine the 3-D ultrastructure with the collagen matrix, the structure and orientation of mineral within bone lamella, and the porosity of bone tissue will be specifically examined. If successful, this method will permit investigations of 3-D bone structure at a resolution that has previously not been possible.

描述（改编自申请人的摘要）：钙沉淀 在人体组织中作为骨骼、牙齿形成的一部分，或在某些 异常过程（即良性或恶性钙化） 乳房、血管斑块、肾脏或胆囊形成的结石等）。 在骨骼中，组织形成了复杂的层次结构， 产生定向材料特性。 传统的显微镜方法有 不适合研究这种三维（3-D）结构，因为 光和高能电子对矿化物的渗透最小 组织。 能量范围为 7 至 11 keV 的 X 射线可穿透小物体 50 至 250 微米尺寸的钙化组织样本 可以允许测量 3-D 分布的特征 矿物质浓度的分辨率为0.1至0.5微米。 3D X 射线显微断层扫描是一种方法，其中多个射线照相视图 从不同方向采集样本并重建数据 用计算机生成一个按比例值组成的数组 (512 x 512 x 256) 样品在许多位置的 X 射线衰减系数。 使用微焦点 X 射线管的方法经常用于研究骨骼 样品尺寸范围为 4 至 20 mm，分辨率为 25 至 125 微米。 使用同步加速器 X 射线源的显微断层扫描能够 更好的分辨率，但探测器的局限性限制了目前的方法 分辨率为2至25微米。 申请人提议研究一种使用 X 射线的方法 同步加速器源（阿贡国家实验室的先进光子源，APS） 实验室）可实现 0.1 至 0.5 微米的分辨率。 一个 使用波带片将 X 射线束聚焦到 建议使用亚微米点。 该方法结合了为 使用较低 X 射线能量的扫描 X 射线显微镜和方法 为使用电子的锥形束断层扫描开发断层扫描重建 束 X 射线源。 所开发的方法将使用湿骨标本进行评估。 这 能够确定胶原蛋白基质的 3-D 超微结构， 骨板内矿物质的结构和方向以及孔隙率 将专门检查骨组织。 如果成功的话，这个方法 将允许以具有以下分辨率的 3D 骨骼结构研究 以前是不可能的。