Tensor Scale-based Methods for Assessment of Trabecular Bone Quality

基于张量尺度的骨小梁质量评估方法

• 批准号: 7874476
• 负责人: PUNAM K. SAHA
• 金额: $ 37.57万
• 依托单位: UNIVERSITY OF IOWA
• 依托单位国家: 美国
• 财政年份: 2009
• 资助国家: 美国
• 起止时间: 2009-06-18 至 2013-05-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7874476
• 关键词: Address; Algorithms; Anisotropy; Architecture; Biomechanics; Bone Density; Bone Diseases; Bone remodeling; Classification; Clinical; Clinical Research; Competence; Complex; Computing Methodologies; Data; Deterioration; Diagnosis; Disease; Disease Progression; Disease regression; Distal; Early Diagnosis; Equilibrium; Experimental Designs; Femur; Fracture; Funding; Goals; Histologic; Human; Image; Image Analysis; Imaging Techniques; Individual; Joints; Laboratories; Laws; Magnetic Resonance Imaging; Measures; Mechanics; Meta-Analysis; Methods; Modeling; Monitor; Noise; Osteogenesis; Osteoporosis; Patients; Performance; Peripheral; Property; Public Health; Radial; Relative (related person); Reproducibility; Research; Research Personnel; Resolution; Risk; Role; Scanning; Shapes; Signal Transduction; Simulate; Site; Skeleton; Specimen; Staging; Stress; Structure; Technology; Testing; Therapeutic Effect; Thick; Three-Dimensional Image; United States National Institutes of Health; Variant; Woman; X-Ray Computed Tomography; base; bone; bone imaging; bone loss; bone mass; bone quality; bone strength; conventional therapy; design; detector; experience; human subject; improved; in vivo; indexing; long bone; men; osteoporosis with pathological fracture; public health relevance; research study; response; retinal rods; spine bone structure; substantia spongiosa

DESCRIPTION (provided by applicant): Trabecular bone (TB) is a complex quasi-random network of interconnected struts and plates. TB constantly remodels to adapt dynamically to the stresses to which it is subjected (Wolff's Law). In osteoporosis, this dynamic equilibrium between bone formation and resorption is perturbed, leading to bone loss and structural deterioration, both increasing fracture risk. Most osteoporotic fractures occur at sites rich in TB (vertebrae, radius, proximal femur). Bone's mechanical competence can only be partly explained by variations in bone mineral density (BMD), which led to the notion of bone quality, chief among which is architecture as a determinant of TB strength. Recent advances in CT and MRI now allow imaging of TB in vivo. However, the limited SNR precludes voxel sizes much smaller than TB thickness, therefore resulting in images that are inherently fuzzy. Therefore, most conventional histomorphometric approaches to TB structure assessment are not applicable to in vivo resolution regime. This proposal introduces a new morphometric index called tensor scale (t-scale) to measure quality of TB micro architecture via in vivo imaging and designs experimental plans to evaluate reproducibility and sensitivity of t-scale-based TB architectural measures. Also, we will examine their strengths to detect TB architectural changes in response to disease or treatment progression. The fundamental principle of t-scale is to fit an ellipsoid to a local structure. The unique property of t-scale is that the ellipsoid's shape, orientation and size simultaneously determine the topology (plates vs. rods), orientation and scale of trabeculae. Our major goals in this project are - (1) to develop the methodology for computing t-scale-based architectural measures from TB images, (2) to evaluate the sensitivity and reproducibility of t-scale-based measures, (3) to examine t-scale measures' ability to predict experimental biomechanical parameters of TB specimens and (4) to examine the sensitivity of t-scale measures to detect the effects of osteoporotic TB loss and antiresorptive treatment via in vivo MRI. The proposed method will (1) obviate the need for binarization, (2) characterize topology, orientation and scale without the need for skeletonization and (3) detect early TB architectural changes in response to treatment or disease progression. The central hypothesis is that the new parameters are more sensitive to detecting remodeling effects and more reproducible than conventional measures. Sensitivity and reproducibility of the new method will be evaluated using synthetic TB networks, micro-CT and ex vivo MR imaging of TB cores from cadaveric distal radii along with experimental biomechanical data, MR images of intact specimens and of human subjects, and finally, patient data from clinical studies previously funded by the NIH. Our objective is to apply t-scale based analysis methods to longitudinal and cross-sectional imaging studies for assessing bone quality. PUBLIC HEALTH RELEVANCE: This project will develop an advanced technology for trabecular bone (TB) quality assessment via in vivo imaging which will enable early detection of TB micro-architectural changes in response to treatment or bone disease including osteoporosis. Osteoporosis is a major public health threat and in the U.S. only, 10 million individuals (eight million are women and two million are men) are estimated to already have the disease and almost 34 million more are estimated to have low bone mass, placing them at increased risk for osteoporosis. The technology proposed in the project will be helpful to diagnose patients at early stage of the disease and routinely monitor their disease status or effects of therapeutic treatments.

描述（由申请人提供）：骨小梁（TB）是由相互连接的支柱和板组成的复杂的准随机网络。结核病不断重塑以动态适应其所承受的压力（沃尔夫定律）。在骨质疏松症中，骨形成和骨吸收之间的动态平衡受到干扰，导致骨质流失和结构恶化，从而增加骨折风险。大多数骨质疏松性骨折发生在结核病丰富的部位（椎骨、桡骨、股骨近端）。骨骼的机械能力只能部分地通过骨矿物质密度 (BMD) 的变化来解释，这导致了骨质量的概念，其中最主要的是作为 TB 强度决定因素的结构。 CT 和 MRI 的最新进展现在可以对结核病进行体内成像。然而，有限的信噪比排除了比 TB 厚度小得多的体素尺寸，因此导致图像本质上模糊。因此，大多数用于结核病结构评估的传统组织形态计量学方法不适用于体内分辨率机制。该提案引入了一种称为张量尺度（t 尺度）的新形态测量指标，通过体内成像测量 TB 微结构的质量，并设计实验计划来评估基于 t 尺度的 TB 结构测量的再现性和灵敏度。此外，我们还将检查它们的优势，以检测结核病结构随疾病或治疗进展而发生的变化。 t 尺度的基本原理是将椭球拟合到局部结构。 t 尺度的独特属性是椭球体的形状、方向和尺寸同时决定小梁的拓扑（板与杆）、方向和尺度。我们在该项目中的主要目标是 - (1) 开发从 TB 图像计算基于 t 尺度的结构测量的方法，(2) 评估基于 t 尺度的测量的敏感性和可重复性，(3) 检查 t 尺度测量预测 TB 标本实验生物力学参数的能力，以及 (4) 检查 t 尺度测量的敏感性以检测骨质疏松的影响 通过体内 MRI 进行结核病消除和抗吸收治疗。所提出的方法将（1）消除二值化的需要，（2）无需骨架化即可表征拓扑、方向和尺度，（3）检测响应治疗或疾病进展的早期结核病结构变化。中心假设是，新参数对检测重塑效果更敏感，并且比传统测量方法更具可重复性。新方法的灵敏度和可重复性将使用合成结核网络、显微 CT 和来自尸体远端半径的结核核心的离体 MR 成像以及实验生物力学数据、完整标本和人类受试者的 MR 图像以及最后来自 NIH 先前资助的临床研究的患者数据来评估。我们的目标是将基于 t 尺度的分析方法应用于纵向和横向成像研究，以评估骨质量。公共健康相关性：该项目将开发一种通过体内成像进行骨小梁 (TB) 质量评估的先进技术，这将能够及早检测 TB 微结构的变化，以应对治疗或包括骨质疏松症在内的骨疾病。骨质疏松症是一个重大的公共卫生威胁，仅在美国，估计就有 1000 万人（800 万人是女性，200 万人是男性）患有这种疾病，还有近 3400 万人的骨量较低，这使得他们患骨质疏松症的风险增加。该项目提出的技术将有助于在疾病的早期诊断患者并定期监测他们的疾病状态或治疗效果。