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)的特征是明显的 一条或多条上肢周围神经的分布，通常发生在 剧烈疼痛的前驱症状。PTS可能是由免疫介导的炎症反应引起的 应激性触发(如劳累、病毒感染)，但其具体发病机制尚不清楚。的确有 PTS的严重残疾负担，多达三分之二的患者报告慢性疼痛 和/或持续性的弱点。 我们团队和其他人最近进行的电诊断和成像研究已经本地化 PTS病变可累及臂丛分支和较多的周围神经。使用高分辨率磁共振成像 和超声(US)技术，我们常规识别固有的“沙漏”收缩(HGC)。 对受累的神经或神经束进行检测，并检测它们供应的肌肉的失神经变化。 目前还没有被接受的治疗方法或已发表的随机对照试验 对PTS免疫调节治疗的评价--仅有少数回顾报道 用类固醇和/或静脉注射免疫球蛋白(IVIg)改善。这归因于 缺乏有效的PTS疾病生物标记物，目前的诊断取决于 临床表现。在顽固性病例中，HGC的手术显微神经松解术有时是 推荐的。我们机构对HGC的术前精确成像定位 促进顽固性病例的靶向微神经溶解，取得了积极的早期结果。Pre- 手术定位减少了与时间密集、广泛的 神经探查和遗漏病理的可能性。 这项研究计划旨在了解影像和血清学的自然过程。 PTS的发现，并确定它们是否可以作为运动和全身的非侵入性标志物 功能恢复。受试者将接受上肢MRI和US检查，以及HGC 结果将与疼痛评分、肌肉力量、电诊断测试、血清学检查相关联 炎症标志物和患者报告的结果测量，都是在初始阶段获得的 每隔3个月和6个月进行一次评估和随访。我们还将评估MRI作为一种潜在的 肌肉失神经的定量生物标志物，可用于预测患者的预后。 经过验证的疾病生物标记物将促进随后的随机试验，包括 药物治疗(如类固醇、静脉注射免疫球蛋白)或外科手术治疗HGCs。及早识别 涉及神经再支配潜力有限或没有潜力的PTS病例(因为 狭窄)可能最终增加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.