Quantitative Magnetic Resonance and Ultrasound Imaging of Human Rotator Cuff Muscle and Tendon

肩袖(RC)是肩关节的主要动力稳定器，功能障碍可导致 通过力偶的丧失，肩部功能的恶化，最终导致关节运动学异常 软骨退变和袖带关节病。全层钢筋混凝土肌腱撕裂很常见，发生在20%的 对于成人人群，当非手术治疗失败时，通常进行外科修复。虽然 肌肉纤维化和肌腱退变是增加手术复杂性和导致 要降低患者的预后评分，很难对它们进行非侵入性评估，包括常规的 磁共振成像(MRI)和超声(US)是使用最广泛的两种成像方式。 最近，新的超短回波时间磁化转移(UTE-MT)磁共振成像技术已经被 开发来评估肌腱质量，初步结果显示对魔角效应不敏感，a 与胶原丢失有很强的相关性，并有能力区分肌腱病组。然而， 脂肪的不同存在降低了该技术在应用于退化肌肉时的准确性，例如 目前已经提出了几种新的脂肪抑制方法。超声定量测定肌肉脂肪和 使用常规B超图像也曾尝试纤维化，但收效甚微。 该计划的目标是开发、优化、验证和翻译新的MRI和US技术 用于全面定量评估RC肌肉和肌腱胶原蛋白的异常和纤维化。在 第一个技术发展目标是优化各种降脂方法的新型UTE-MT，并 实施后，将确定参数优化后的上级版本。此外，数量上的 将实施基于原始射频数据的US，并将建立新的组织特定散射模型 已创建。第一个假设是具有脂肪抑制和定量超声的新型定量UUT-MT 结合肌腱和肌肉的特定组织模型可以开发和优化。在第二个目标中， 采用大鼠一侧RC肌腱大面积撕裂的对照模型，诱导肌肉和肌腱退变。 新的定量MRI和US技术将得到验证，并与现有的定量技术进行比较 技巧。第二个假设是，这些新技术可以纵向实施，即 可重复性，并将更好地与参考标准组织学测量相关联。第三个人类 Translative Aim将这些新技术带入临床。两个年龄和性别匹配的患者队列 将被成像，包括没有全厚度RC撕裂的个体和具有全厚度RC撕裂的个体 世卫组织将通过获取小样本进行外科修复。第三个假设是这部小说 定量MRI和US技术可以转化到临床上进行全面的、非侵入性的评估 由RC肌肉和肌腱组成。

The rotator cuff (RC) is the primary dynamic stabilizer of the glenohumeral joint and dysfunction can lead to abnormal joint kinematics through loss of force couples, deterioration of shoulder function, and ultimately cartilage degeneration and cuff arthropathy. Full-thickness RC tendon tears are common, occurring in >20% of the adult population, and when non-operative management fails, surgical repair is often performed. Although muscle fibrosis and tendon degeneration are important variables that can increase surgical complexity and lead to lower patient outcome scores, they are difficult to evaluate non-invasively, including with conventional magnetic resonance imaging (MRI) and ultrasound (US), the two most widely used imaging modalities. Recently the novel ultrashort echo time magnetization transfer (UTE-MT) MRI technique has been developed to assess tendon quality, and preliminary results showed insensitivity to the magic angle effect, a strong correlation with collagen loss, and the capability to distinguish between tendinopathy groups. However, the variable presence of fat diminishes the accuracy of the technique when applied to degenerated muscle, for which several new fat-suppression methods have been proposed. Ultrasound quantification of muscle fat and fibrosis has also been attempted using routine B-mode images with limited success. The goal of this proposal is to develop, optimize, validate, and translate novel MRI and US techniques for comprehensive quantitative evaluation of RC muscle and tendon collagen abnormalities and fibrosis. In the first technical development aim, novel UTE-MT with various fat-suppression methods will be optimized and implemented, and the superior version with optimized parameters will be determined. In addition, quantitative US based on raw radiofrequency data will be implemented and novel tissue-specific scattering models will be created. The first hypothesis is that novel quantitative UTE-MT with fat-suppression and quantitative US incorporating tissue-specific models for tendon and muscle can be developed and optimized. In the second aim, a controlled rat model with unilateral massive RC tendon tear is used to induce muscle and tendon degeneration. The novel quantitative MRI and US techniques will be validated and compared alongside existing quantitative techniques. The second hypothesis is that these novel techniques can be implemented longitudinally, are reproducible, and will better correlate with reference standard histological measurements. The third human translational aim brings these new techniques to the clinic. Two age- and gender-matched cohorts of patients will be imaged, including individuals without full-thickness RC tears and individuals with full-thickness RC tears who will undergo surgical repair with acquisition of small biopsy samples. The third hypothesis is that the novel quantitative MRI and US techniques can be translated to the clinic for comprehensive, non-invasive assessment of RC muscle and tendon.