Non Invasive Characterization of Bone Microdamage

骨微损伤的非侵入性表征

• 批准号: 6579616
• 负责人: DANIEL P NICOLELLA
• 金额: $ 16.65万
• 依托单位: SOUTHWEST RESEARCH INSTITUTE
• 依托单位国家: 美国
• 财政年份: 2002
• 资助国家: 美国
• 起止时间: 2002-09-24 至 2005-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6579616
• 关键词: bone density; bone fracture; femur; histochemistry /cytochemistry; human tissue; noninvasive diagnosis; normal ossification; nuclear magnetic resonance spectroscopy; skeletal stress; technology /technique development; tensile strength

DESCRIPTION (provided by applicant): Humans experience an age-related increase in the incidence of skeletal fractures and this increase may be due to a variety of factors including a decrease in bone mineral density, impaired balance and reflexes, changes in the shape and size of bones, changes in bone porosity and microarchitecture, alterations in bone mineral and organic constituents, and microdamage accumulation. The latter three factors, often referred to as "bone quality," are increasingly recognized as important determinants of fracture risk, especially for osteoporotic patients. Quantification of measures of bone quality such as microdamage accumulation and other microstructural characteristics may lead to a more accurate measure of bone strength and therefore fracture risk. Unfortunately, current technology does not allow the nondestructive and non-invasive detection of cortical bone microdamage or other measures of bone quality including microporosity. On the other hand, NMR proton spin-spin (T2) or spin-lattice (T1) relaxation time measurements and analytical processing techniques have been used to determine microstructural characteristics including porosity, pore size distribution, and permeability of various types of fluid filled porous materials with characteristic pore sizes ranging from sub-micron to sub-millimeter. We propose to develop a rapid, non-destructive and non-invasive technique based on low field pulsed NMR to detect and quantify bone microdamage and porosity and relate these measurements to bone mechanical properties. This new information may then be used in combination with or replace existing methods to more accurately assess fracture risk. The objective of the proposed research project is to develop a non-destructive technique to assess bone quality by quantifying microdamage, porosity, and pore size distribution in cortical bone. The major hypothesis to be tested in this proposal is that non-invasive NMR relaxation time measurements can be used to characterize cortical bone microdamage, porosity, and pore size distribution (measures of bone quality) and can subsequently augment or replace traditional bone mineral measurements to predict cortical bone mechanical properties. We expect our findings will allow the non-destructive and possibly in-vivo assessment of cortical bone microdamage and porosity and correlate these measures of cortical bone quality to cortical bone strength. Although this is a high-risk proposal, this new knowledge will be significant since it may ultimately lead to the development of a more accurate, less complicated, and less expensive technique to clinically assess the risk of fracture compared to currently available technology.

描述（由申请人提供）： 人类经历了与年龄相关的骨骼骨折发生率的增加，这种增加可能是由于多种因素所致，包括骨矿物质密度的降低，平衡和反射性受损，骨骼的形状和大小的变化，骨孔隙度和微体系结构的变化，骨矿物质和有机成分以及微型成分的变化。后三个因素（通常称为“骨质”）越来越被认为是骨折风险的重要决定因素，尤其是对于骨质疏松患者而言。量化骨质质量的测量，例如微型塑料积累和其他微结构特征，可能会导致更准确的骨强度衡量，从而使骨折风险。不幸的是，当前的技术不允许对皮质骨微塑料或其他骨质质量的无创和非侵入性检测，包括微孔。另一方面，NMR质子旋转自旋（T2）或自旋晶格（T1）松弛时间测量和分析处理技术已用于确定微结构特性，包括孔隙率，孔径分布和各种类型流体填充的多孔填充的多孔毛孔材料，其特征性的孔隙尺寸具有从亚米克斯底部到亚米尔米计的特征性孔径。我们建议基于低场脉冲NMR开发一种快速，无损和非侵入性技术，以检测和量化骨微痕迹和孔隙率，并将这些测量结果与骨骼机械性能相关联。然后，可以将此新信息与现有方法结合使用，以更准确地评估断裂风险。拟议的研究项目的目的是开发一种非破坏性技术，以通过量化皮质骨中的微型塑料，孔隙率和孔径分布来评估骨骼质量。在该提案中要测试的主要假设是，非侵入性NMR松弛时间测量可用于表征皮质骨微型磨物，孔隙率和孔径分布（骨质质量的测量），然后可以增加或更换传统的骨矿物测量值，以预测皮层骨骼机械性能。 我们预计我们的发现将允许对皮质骨微塑料和孔隙率的非破坏性和可能的​​体内评估，并将这些皮质骨质量的测量与皮质骨强度相关联。尽管这是一个高风险的建议，但这种新知识将很重要，因为它最终可能导致一种更准确，更复杂且价格较低的技术的发展，从而在临床上评估与当前可用技术相比，临床评估骨折的风险。