Digital Tomosynthesis-Based Microstructural Measures to Predict Vertebral Fragili

描述（由申请人提供）：骨质疏松症引起的骨折是一个严重的问题。椎骨骨折是最常见的;两个女人中的每个人在一生中至少有一个椎骨骨折。定量评估骨折风险的金标准是骨矿物质密度（BMD）。然而，从BMD预测骨折风险的成功有限。已知松质骨的其他显微结构特性有助于定量评估椎体骨质量和预测骨强度。 然而，这些在人体脊柱中难以在体内测量。数字断层合成（Digital Tomosynthesis，简称TOM）是一种允许对物体中的聚焦平面进行成像的技术。由物体的其他平面引起的图像模糊会使使用X射线胶片的定量分析非常困难，这种模糊在很大程度上减少了。在单次重复扫描期间连续获取图像允许收集一系列图像，每个图像聚焦在对象的不同平面上。这提供了一系列X射线胶片的数字等效物，这些X射线胶片将从对象的物理切片获得。此外，CT具有良好的平面内分辨率，快速，相对便宜，并且使患者暴露于比CT扫描更低的辐射剂量。已经发现具有临床意义并且与椎骨的重要机械特性相关的松质骨的微观结构/纹理参数适合于可以在MRI图像上执行的分析。然而，骨密度尚未被检查其在骨质量定量分析中的价值。因此，我们的总体目标是开发基于MRI成像的椎骨脆性和骨折风险的改进标记物。在此期间，我们提出了一个体外研究，以探讨的可行性，量化的椎骨骨微结构和预测椎骨骨衰竭的性质，使用人尸体椎骨骨。本研究的具体目标是：1）使用人体尸体椎骨，确定感兴趣区域的大小和平面，以最大限度地提高骨密度和显微计算机断层扫描（？）CT）参数，并校准CT与？CT. 2)使用人类尸体的椎骨，？CT、DEXA、HRCT、MRI和力学测试，以确定基于DTS的显微结构变异性预测椎体强度和脆性的程度。3)使用人类尸体的椎骨，？CT、DEXA、HRCT、MRI和力学测试确定了基于DTS的显微结构变异性预测椎体蠕变的程度。 公共卫生相关性：该项目旨在确定临床可用成像系统的新应用，即数字断层合成，是否可用于测量椎骨的微观结构特性并预测椎骨的强度、脆性和变形。研究结果将被用于确定参数，这些参数可以更有效地估计椎骨骨折风险和恢复骨结构的策略。从这项研究中获得的知识可能会大大改变我们预测骨折风险和治疗骨质疏松症的临床方法，骨质疏松症是一种对老年人群有很大影响的疾病。

DESCRIPTION (provided by applicant): Bone fractures attributable to osteoporosis are a significant problem. Vertebral fractures are among the most common; everyone in two women is expected to have at least one vertebral fracture in their lifetime. The gold-standard for quantitative assessment of fracture risk is bone mineral density (BMD). However, prediction of fracture risk from BMD has had limited success. Additional microstructural properties of cancellous bone are known to contribute to the quantitative assessment of vertebral bone quality and prediction of bone strength. However, these are difficult to measure in human spine in vivo. Digital tomosynthesis (DTS) is a technique that allows for imaging of focused planes in objects. The blurring in the image that is caused by other planes of the object which would make quantitative analysis using an x-ray film very difficult is reduced to a great extent in DTS. The successive acquisition of images during a single DTS scan allows for collection of a series of images each of which is focused on a different plane of the object. This provides a digital equivalent of a series of x-ray films that would be obtained from physical slices of the object. Furthermore, DTS has a good in-plane resolution, fast, relatively cheap and exposes the patient to a lower radiation dose than a CT scan. The microstructure/texture parameters of cancellous bone that have been found to have clinical significance and related to important mechanical properties of vertebrae are amenable to analyses that can be performed on DTS images. However, DTS has not been examined for its value in quantitative analysis of bone quality. Therefore, our overall goal is to develop improved markers of vertebral bone fragility and fracture risk based on DTS imaging. In this period, we propose an in vitro study to examine the feasibility of DTS for quantification of vertebral bone microstructure and for predicting vertebral bone failure properties using human cadaveric vertebrae. The specific goals of the proposed period are: 1) Using human cadaver vertebrae, determine the size and plane of regions of interest for DTS analysis that maximize correlation between DTS and microcomputed tomography (?CT) parameters, and calibrate DTS with ?CT. 2) Using human cadaver vertebrae, ?CT, DEXA, HRCT, DTS and mechanical testing, to determine the extent to which DTS-based microstructural variability predicts vertebral strength and brittleness. 3) Using human cadaver vertebrae, ?CT, DEXA, HRCT, DTS and mechanical testing, determine the extent to which DTS-based microstructural variability predicts vertebral creep. PUBLIC HEALTH RELEVANCE: This project is designed to determine whether a new application of a clinically available imaging system, namely digital tomosynthesis, can be used to measure vertebral bone microstructural properties and predict vertebral strength, brittleness and deformation. The results will be used to define parameters that can be more effective in estimating vertebral fracture risk and strategies to restore bone structure. The knowledge gained form this research may substantially change our clinical approach for predicting risk of fracture and treating osteoporosis, a disease with a large impact on the elderly population.