MRI T2 Relaxation Time as a Predictor of Osteoarthritis

描述（由申请人提供）：骨关节炎（OA）是一种退行性关节疾病，仅在美国就有超过2700万人受到影响。尽管OA是一种广泛存在且使人衰弱的疾病，但目前的治疗选择极其有限，并且不存在既定的疾病改善疗法。可以预防OA发作并阻止其进展的疗法的开发取决于用于早期疾病检测的非侵入性生物标志物的发现。虽然MRI可用于非侵入性地可视化OA中的形态学关节退行性变，但最近的MRI发展显示出在形态学退行性变之前检测软骨中的早期生化变化的前景。一种先进的MRI技术，称为T2弛豫时间映射，对软骨的早期生化变化敏感，并有可能早期诊断OA。该研究旨在评估没有疼痛但有发生OA风险的受试者的软骨T2弛豫时间。初步研究表明，软骨T2的空间分布与OA受试者的疼痛进展有关，这是一个有希望的结果。拟议研究的结果将是有价值的，因为它们将有助于确定软骨中的早期生化变化，如通过T2映射参数量化的，是否可以预测症状性膝关节OA的发作。为了解决这个问题，提出了以下三个具体目标：目标1：跨部门分析。确定OAI发病队列患者中使用T2弛豫时间的平均值、空间分布和层状组织量化的软骨生化成分与软骨、半月板和骨髓中的形态学膝关节退变之间的关系。目标2：前瞻性分析。确定基线软骨生化成分是否可以预测症状性膝关节OA的存在，症状性膝关节OA定义为两年后疼痛的发展和软骨、半月板和骨髓中形态学变性的增加。目标3：纵向分析。确定软骨生化成分的变化是否与症状性膝关节OA的存在相关。 公共卫生相关性：该项目的最终目标是评估软骨生化成分之间的关系，如通过新的MRI技术（特别是T2映射）和软骨形态的纵向变化进行量化。将对骨关节炎倡议（OAI）发病率队列中有发生骨关节炎风险的受试者进行研究。本研究的结果将是评价MRI T2作为骨关节炎早期软骨退变标志物的作用不可或缺的。

DESCRIPTION (provided by applicant): Osteoarthritis (OA) is a degenerative joint disease, affecting more than 27 million people in the United States alone. Despite the fact that OA is a widespread and debilitating disease, current treatment options are extremely limited and no established disease-modifying therapies exist. The development of therapies that can prevent the onset OA and halt its progression is contingent upon the discovery of non-invasive biomarkers for early disease detection. While MRI can be used to non-invasively visualize morphologic joint degeneration in OA, recent MRI developments show promise for the detection of early biochemical changes in cartilage, prior to the morphologic degeneration. An advanced MRI technique, called T2 relaxation time mapping, is sensitive to early biochemical changes in cartilage and has the potential for early diagnosis of OA. The proposed study aims to evaluate cartilage T2 relaxation time in subjects who have no pain, but are at risk for the development of OA. Preliminary studies have shown promising results linking the spatial distribution of cartilage T2 to the progression of pain in subjects with OA. The results of the proposed study will be valuable in that they will help determine whether early biochemical changes in cartilage, as quantified by T2 mapping parameters, can predict the onset of symptomatic knee OA. In order to address this topic, the following three specific aims are proposed: Aim 1: Cross-sectional Analysis. To determine the relationship between cartilage biochemical composition as quantified using the mean, spatial distribution, and laminar organization of T2 relaxation time, and morphologic knee joint degeneration in the cartilage, meniscus and bone marrow, in patients from the OAI incidence cohort. Aim 2: Prospective Analysis. To determine whether baseline cartilage biochemical composition can predict the presence of symptomatic knee OA, defined as development of pain and an increase in morphologic degeneration in the cartilage, meniscus, and bone marrow after two years. Aim 3: Longitudinal Analysis. To determine whether changes in cartilage biochemical composition are related to the presence of symptomatic knee OA. PUBLIC HEALTH RELEVANCE: The ultimate goal of this project is to assess the relationship between cartilage biochemical composition, as quantified by novel MRI techniques (specifically T2 mapping), and longitudinal changes in cartilage morphology. Subjects from the Osteoarthritis Initiative (OAI) incidence cohort, who are at risk for developing osteoarthritis, will be investigated. The results of this study will be integral in evaluating the role of MRI T2 as a marker for early cartilage degeneration in osteoarthritis.