Magnetic resonance and ultrasound imaging as biomarkers for detection and monitoring of Parsonage-Turner Syndrome (PTS)

项目摘要 Parsonage-Turner综合征（PTS）的特征是在 一个或多个上肢周围神经的分布，并且通常在 剧烈疼痛前驱症状。PTS可能是由免疫介导的炎症反应引起的， 应激触发（如劳累、病毒感染），但其具体发病机制尚不清楚。有 PTS中的显著残疾负担，高达三分之二的患者报告慢性疼痛 和/或持续性虚弱。 我们小组和其他人最近的电诊断和成像研究已经定位了 PTS病变以臂丛神经分支及周围神经较多。使用高分辨率MRI 和超声（US）技术，我们常规识别内在的，'沙漏'收缩（HGC） 的参与神经或神经束，并检测其供应的肌肉的去神经变化。 目前尚无公认的治疗方法或已发表的随机对照试验 评估免疫调节治疗PTS，只有少数回顾性报告， 类固醇和/或静脉注射免疫球蛋白（IVIg）改善。这归因于 缺乏有效的PTS疾病生物标志物，目前的诊断取决于 临床表现在复发病例中，HGC的显微神经松解术有时 推荐在我们的机构中，HGC的精确术前成像定位 促进靶向显微神经松解术在脊髓炎的情况下，积极的早期结果。预处理 手术定位降低了与时间密集、广泛的 神经探查和可能遗漏病理学检查 本研究计划旨在了解影像学和血清学的自然过程， PTS的结果，并确定它们是否可以作为运动和整体的非侵入性标志物 功能恢复受试者将接受上肢MRI和US，以及HGC 结果将与疼痛评分、肌肉力量、电诊断测试、血清学 炎症标志物和患者报告的结局指标，均在初始 评估和随访间隔3个月和6个月。我们还将评估MRI作为一种潜在的 肌肉去神经支配的定量生物标志物，可用于预测患者的结果。 经验证的疾病生物标志物将促进随后的随机试验，包括 药物治疗（如类固醇、IVIg）或HGC的手术显微神经松解术。及早识别 涉及神经再支配潜力有限或没有潜力的PTS病例（由于 缩窄）可以最终增加显微神经松解术的成功率。

Project Abstract Parsonage-Turner Syndrome (PTS) is characterized by marked weakness in the distribution of one or more upper extremity peripheral nerves and typically ensues following an intense pain prodrome. PTS likely arises from an immune-mediated, inflammatory response to a stressful trigger (e.g. exertion, viral infection), but its specific pathogenesis is unknown. There is a significant burden of disability in PTS, with up to two-thirds of patients reporting chronic pain and/or persistent weakness. Recent electrodiagnostic and imaging research by our group and others has localized PTS lesions to brachial plexus branches and more peripheral nerves. Using high-resolution MRI and ultrasound (US) techniques, we routinely identify intrinsic, ‘hourglass’ constrictions (HGCs) of involved nerves or nerve fascicles and detect denervation changes in muscles they supply. There is no currently accepted treatment or published randomized, controlled trial evaluating immunomodulatory therapy for PTS, with only a few retrospective reports of improvement with steroids and/or intravenous immunoglobulin (IVIg). This is attributed to the absence of a validated disease biomarker for PTS, with the diagnosis currently hinging on the clinical presentation. In recalcitrant cases, surgical microneurolysis of the HGC is sometimes recommended. Precise, pre-operative imaging localization of HGCs at our institution has facilitated targeted microneurolysis in recalcitrant cases, with positive early results. Pre- operative localization reduces potential morbidity associated with a time-intensive, extensive nerve exploration and the possibility of missing pathology. This research plan aims to understand the natural course of imaging and serologic findings in PTS and to determine if they can serve as non-invasive markers of motor and overall functional recovery. Subjects will undergo MRI and US of their upper extremities, and HGC findings will be correlated with pain scores, muscle strength, electrodiagnostic testing, serologic inflammatory markers, and patient reported outcome measures, all obtained upon initial evaluation and at follow-up intervals of 3 and 6 months. We will also evaluate MRI as a potential quantitative biomarker of muscle denervation that can be used to predict patient outcomes. Validated disease biomarkers would facilitate a subsequent randomized trial comprising medical therapy (e.g. steroids, IVIg) or surgical microneurolysis of HGCs. Early identification of PTS cases involving nerves that have limited or no potential for reinnervation (because of constrictions) may ultimately increase the success of microneurolysis.