Correlation of MRI with Cartilage Mechanical Stiffness

MRI 与软骨机械刚度的相关性

• 批准号: 6908265
• 负责人: MARTHA L GRAY
• 金额: $ 28.86万
• 依托单位: BETH ISRAEL DEACONESS MEDICAL CENTER
• 依托单位国家: 美国
• 财政年份: 2003
• 资助国家: 美国
• 起止时间: 2003-07-15 至 2007-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6908265
• 关键词: articular cartilage; biochemistry; bioimaging /biomedical imaging; biomechanics; clinical research; collagen; elasticity; extracellular matrix; fluid flow; human tissue; image processing; joint stiffness; magnetic resonance imaging; mathematics; method development; mucopolysaccharides; musculoskeletal imaging /visualization /scanning; stimulus /response

DESCRIPTION (provided by applicant): The past decade has seen tremendous growth in efforts to establish noninvasive assessments of articular cartilage, motivated by a need to evaluate the efficacy of therapeutic interventions and to understand disease progression. The main tool in this regard is magnetic resonance imaging (MRI), which has emerged as the preferred means of imaging cartilage anatomy, and underlies the developing methods for imaging cartilage biochemical properties. Though anatomy and biochemistry of cartilage are undeniably important metrics, the sine qua non of cartilage functional integrity is its mechanical properties. The hypothesis to be examined in this proposal is that a spatial map computed from a combination MRI-derived biochemical metrics will correspond to spatially-localized mechanical properties. Preliminary studies using three human tibial plateau samples showed a strong correlation between a spatial map of GAG concentration (measured by MRI) and a corresponding map of mechanical stiffness (measured by indentation studies), suggesting the potential for MRI to provide a noninvasive measure of the cartilage mechanical properties. To build on these exciting preliminary data we aim to: 1. Evaluate whether the correlation between GAG and arthroscopic-probe indentation behavior is sustained as sample number is increased and whether the correlation is improved by considering an additional an MRI measure (T2) known to be influenced by collagen. 2. Evaluate the three regimes of mechanical behavior to see whether they have the same dependency on the biochemically-based MR metrics. The proposed studies represent an essential and new step towards functional imaging of cartilage. Importantly, the relatively new MR methodologies that reflect tissue biochemical properties provide the enabling technology that opens up this avenue of research. The spatially-localized information provided here would be potentially valuable in a myriad of contexts ranging from aiding our basic understanding of the macromolecular mechanism conferring cartilage stiffness, to the practical clinical question of identifying whether tissue is functionally competent.

描述（由申请人提供）：过去十年，出于评估治疗干预效果和了解疾病进展的需要，建立关节软骨无创评估的努力取得了巨大进展。这方面的主要工具是磁共振成像（MRI），它已成为软骨解剖成像的首选手段，并且是软骨生化特性成像方法开发的基础。尽管软骨的解剖学和生物化学无疑是重要的指标，但软骨功能完整性的必要条件是其机械性能。本提案要检验的假设是，根据 MRI 衍生的生化指标组合计算出的空间图将对应于空间局部的机械特性。使用三个人类胫骨平台样本的初步研究表明，GAG 浓度的空间图（通过 MRI 测量）与相应的机械刚度图（通过压痕研究测量）之间存在很强的相关性，这表明 MRI 有可能提供非侵入性测量软骨的机械性能。为了建立在这些令人兴奋的初步数据的基础上，我们的目标是： 1. 评估随着样本数量的增加，GAG 和关节镜探针压痕行为之间的相关性是否持续存在，以及通过考虑已知的额外 MRI 测量 (T2) 是否可以改善相关性。受胶原蛋白的影响。 2. 评估机械行为的三种机制，看看它们是否对基于生化的 MR 指标具有相同的依赖性。拟议的研究代表了软骨功能成像的重要且新的一步。重要的是，反映组织生化特性的相对较新的 MR 方法提供了开辟这一研究途径的支持技术。这里提供的空间定位信息在许多情况下都具有潜在价值，从帮助我们对赋予软骨刚度的大分子机制的基本理解，到识别组织是否具有功能能力的实际临床问题。