T1P MRI OF ARTICULAR CARTILAGE FOLLOWING VISCOSUPPLEMENTATION

这个子项目是利用资源的许多研究子项目之一。 由NIH/NCRR资助的中心拨款提供。对子项目的主要支持 子项目的首席调查员可能是由其他来源提供的， 包括美国国立卫生研究院的其他来源。为子项目列出的总成本可能 表示该子项目使用的中心基础设施的估计数量， 不是由NCRR赠款提供给次级项目或次级项目工作人员的直接资金。 膝骨性关节炎(OA)影响着大约2700万美国人，占初级保健医生就诊人数的很大一部分。对于轻微的症状，治疗包括减肥、活动调节、物理治疗和注射。粘液补充(VS)现在被常规提供给轻到中度疾病的患者，通常是在类固醇注射无效后。在一些人中，VS后的疼痛缓解可以持续六个月以上。到目前为止，还没有治疗剂被证明可以改变骨关节炎的疾病进展；然而，缺乏设计良好的研究来分析制剂对关节软骨的影响。目前尚不清楚临床治疗反应的某些成分是否源于通过修复软骨基质而对退行性软骨产生的结构和生理影响，以及关节接触面的机械作用和关节内的抗炎作用。 目前对VS对人软骨影响的研究大多采用滑液分析软骨退变的标志物、滑膜组织活检等间接分析手段。我们建议使用先进的MRI成像来连续分析VS后关节软骨蛋白多糖和水分含量的变化。体外分析表明，这些标记物与组织的机械完整性相关，因此可以提供疾病进展和/或逆转的敏感标记物。应用影像技术深入了解软骨生物化学，将极大地促进VS发病机制的研究。 我们建议用T1？MRI成像方法评估注射前后的膝关节软骨，以证明透明质酸对轻中度膝关节骨性关节炎(Kellgren-Lawrence分级I级和II级)患者关节软骨蛋白多糖含量和特征的影响。使用T1？松弛常数，可以获得软骨的详细图像，给出体积测量和关于软骨基质中蛋白多糖含量变化的信息。本研究试图应用这些技术来评估VS对膝关节软骨的影响。

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. Primary support for the subproject and the subproject's principal investigator may have been provided by other sources, including other NIH sources. The Total Cost listed for the subproject likely represents the estimated amount of Center infrastructure utilized by the subproject, not direct funding provided by the NCRR grant to the subproject or subproject staff. Knee osteoarthritis (OA) affects roughly 27 million Americans and accounts for a significant number of visits to primary care physicians. For mild symptoms, treatment consists of weight loss, activity modification, physical therapy, and injections. Viscosupplementation (VS) is now routinely offered to patients with mild to moderate disease, usually after response failure to steroid injections. Pain relief following VS can last upwards of six months in some individuals. As of yet, no therapeutic agent has been shown to modify the disease progression of osteoarthritis; however, well-designed studies analyzing agents effects on articular cartilage are lacking. It is unclear whether some component of the clinical response to treatment is due to a structural and physiological effect on degenerative cartilage by restoring its matrix, in addition to a mechanical effect on joint contact surfaces and anti-inflammatory effect within the joint. Most current studies of the effects of VS on human cartilage use synovial fluid analysis for markers of cartilage degeneration, synovial tissue biopsy, and other indirect means of analysis. We propose the use of advanced MRI imaging to serially analyze articular cartilage following VS for changes in proteoglycan and water content. In vitro analysis suggests that these markers are correlates of the mechanical integrity of the tissue, and as such, can provide sensitive markers of disease progression and/or reversion. Having insight into cartilage biochemistry using imaging techniques will greatly advance investigations into the mechanism of VS. We propose T1¿ MRI imaging modalities to evaluate knee cartilage before and after injections to document the effect of hyalumonic acid on the proteoglycan content and character of articular cartilage in patients with mild to moderate OA of the knee (Kellgren-Lawrence Grades I and II). Using the T1¿ relaxation constant, detailed images of cartilage can be obtained, giving volumetric measurements and information on changes in proteoglycan content of the cartilage matrix. This study will attempt to apply these techniques to assess the effect of VS on knee cartilage.