Quantitative shoulder MRI for evaluating rotator cuff pathology

项目摘要/摘要 肩袖撕裂是上肢疼痛和残疾的常见来源，在 老年人口。对于非手术治疗失败的患者，通常会考虑手术治疗。 管理人员，有急性撕裂，或不能参加正常的日常活动，尽管他们的过程 理疗。然而，肩袖手术后肌腱愈合失败是常见的并发症。多重 研究表明，术前泪液大小、患者年龄和肌肉质量是影响预后的关键因素。 确定手术结果，但需要改进的非侵入性评估方法来评估 肌腱和肌肉质量来确定最佳治疗策略。 这个研究项目的目标是开发定量的mri方法来评估肌腱和肌肉。 质量，评估已开发的MRI方法对变性的敏感性，并与组织学进行比较 分析，并评估手术后肌腱和肌肉质量的变化。首先，定量超短回波- 将开发时间方法来评估由高度有序的胶原组成的肩袖肌腱 纤维结构导致较短的T2弛豫时间。量化的参数将在以下情况下进行比较 对照组和有全层肩袖撕裂的患者，并将MR定量与半定量 对患者组在手术期间采集的肌腱样本进行定量组织学分级。第二，肌肉 定量成像技术将被开发用于两个不同的目的，以评估纤维化和脂肪部分 同时将脂肪组织区分为米色或白色脂肪。肌肉纤维化还没有被量化 这在很大程度上是因为它的T2*松弛时间很短，但UTE多回波图像将允许对肌肉进行量化 纤维化症也有。肌腱撕裂后肩袖肌肉中可能存在米色脂肪 这一点很重要，因为米色脂肪可以促进肌肉再生和愈合。我们还将发展 准确的脂肪量化技术，定义米色脂肪。第三，将对患者进行纵向研究 应用发达肌腱和肌肉评价手术前后全层肩袖撕裂 技术，以及肌腱和肌肉质量的变化，手术将进行评估。统计分析以 确定影响临床功能结果的重要成像指标也将被执行。这项建议 方法包括结构、微结构和生化变化的综合生物标记物，以及目的 用于全定量成像，以进行更准确的评估。 建议的研究和培训计划是为候选人在以下方面获得进一步知识而设计的 肌肉骨骼生物学和统计学，以及临床研究设计和方法学方面的专业知识，同时 扩展她的核磁共振技术技能。K01资助奖将帮助候选人成为独立的成像师 肌肉骨骼领域的科学家。

PROJECT SUMMARY/ABSTRACT Rotator cuff tears are a common source of pain and disability in the upper extremity, occurring up to 50-80% in an elderly population. Surgical treatment is normally considered for patients who fail in non-operative management, have an acute tear, or are unable to participate in their normal daily activities despite a course of physical therapy. However, failure of tendon healing after rotator cuff surgery is a common complication. Multiple studies have demonstrated that preoperative tear size, patient age, and muscle quality are critical factors to determine surgical outcomes, but there is a need for improved non-invasive evaluation methods to assess tendon and muscle quality to determine optimal treatment strategy. The goals of this research project are to develop quantitative MRI methods for evaluating tendon and muscle quality, to assess the sensitivity of developed MRI methods to degeneration in comparison to histological analysis, and to evaluate tendon and muscle quality changes due to surgery. First, quantitative ultrashort echo- time methods will be developed to evaluate the rotator cuff tendons, which consist of highly-ordered collagen fiber structures resulting in a short T2 relaxation time. The quantified parameters will be compared between controls and patients having full-thickness rotator cuff tears, and MR quantification will be compared with semi- quantitative histologic grades of tendon samples acquired during surgery for the patient group. Second, muscle quantitative imaging techniques will be developed for two different purposes, to evaluate fibrosis and fat fractions simultaneously and to discriminate fat tissue as either beige or white fat. Muscle fibrosis has not been quantified much due to its short T2* relaxation time, but UTE multi-echo images will allow the quantification of muscle fibrosis as well. A potential of the presence of beige fat in the rotator cuff muscles after tendon tears has been shown, which is important because beige fat can promote muscle regeneration and healing. We will also develop accurate fat quantification technique to define beige fat. Third, a longitudinal study will be performed with patients having full-thickness rotator cuff tears before and after surgery using developed tendon and muscle evaluation techniques, and tendon and muscle quality changes due to surgery will be evaluated. Statistical analysis to determine important imaging metrics that affect clinical functional outcomes will be performed, too. This proposed approach includes comprehensive biomarkers of structural, micro-structural, and biochemical changes, and aims for fully quantitative imaging for more precise assessments. The proposed research and training plans are designed for the candidate to gain further knowledge in musculoskeletal biology and statistics, and expertise in clinical research design and methodologies while extending her MRI technical skills. The K01 grant award will help the candidate to be an independent imaging scientist in the musculoskeletal field.