Quantitative Assessment of Peripheral Nerve Injury and Repair via Multi-Parametric MRI

通过多参数 MRI 定量评估周围神经损伤和修复

• 批准号: 10057154
• 负责人: Richard Dortch
• 金额: $ 21.61万
• 依托单位: ST. JOSEPH'S HOSPITAL AND MEDICAL CENTER
• 依托单位国家: 美国
• 财政年份: 2016
• 资助国家: 美国
• 起止时间: 2016-08-01 至 2021-04-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10057154
• 关键词: Quantitative; Assessment; Peripheral; Nerve; Injury

PROJECT SUMMARY The overall goal of this proposal is to develop and evaluate a multi-parametric set of quantitative MRI (qMRI) tools for monitoring the microstructural changes associated with traumatic peripheral nerve injury (TPNI) and subsequent surgical repair. Up to 5% of all admissions to level I trauma centers have a TPNI; and a significant increase in the incidence of TPNI has been noted in recent military missions. Common etiologies include trauma to limbs from penetrating injury, crush, stretch, and ischemia. Clinical management of TPNI faces two limitations: i) the inability to acutely identify injuries that require surgery (e.g., nerve lacerations) and ii) the inability to detect failed nerve surgeries prior to muscle re-innervation—may take months or years depending on the injury site. Due to these limitations, physicians are required to a “wait and watch” using qualitative measures obtained from patient history and physical exam. This results in delayed management and increased instances of permanent motor/sensory loss. Quantitative MRI (qMRI) techniques may provide a non-invasive, quantitative characterization of nerve microstructure in vivo following trauma and throughout the recovery process (i.e., prior to muscle re-innervation). We propose to develop and evaluate qMRI techniques for this purpose. If successful, these strategies could improve outcomes by i) identifying patients that require surgery and ii) identifying surgical failures earlier than current techniques, even guiding re-operation. The proposed qMRI methods will be developed and evaluated as potential biomarkers of nerve recovery via human studies in the median/ulnar nerves of the forearm and wrist. We will first develop and optimize qMRI methods of these nerves (Aim 1). MRI of peripheral nerves is challenging due a number of factors, including the need for fast, high-resolution imaging and the influence of fat. The PI has previously shown success in developing and optimizing qMRI methods to evaluate inherited neuropathies. Here, we will build upon these previous developments and employ quantitative magnetization transfer and diffusion imaging to assay Wallerian degeneration and axonal outgrowth following injury/repair, respectively. We have shown that inflammation confounds diffusion-based assessments of nerve recovery in a rat model of trauma. As a result, we will also evaluate models the account for the influence of inflammation. Once optimized, we will perform cross-sectional studies (Aim 2) in patients with nerve injuries of varying severity to evaluate the ability of qMRI to identify injuries that require surgery. We will also perform longitudinal studies (Aim 3) following surgery to evaluate the ability of qMRI to monitor nerve regeneration, with results compared to EMG/NCS and function (e.g., grip strength). Finally, we will explore MRI methods to monitor the downstream effects of TPNI on skeletal muscle, as this information may improve future revisional surgery recommendations when failed repairs are detected. Specifically, we will measure T2/fat-fraction (reports on acute/chronic denervation) in muscles innervated by the median/ulnar nerves (e.g., muscles of the hand) to assess their viability after nerve repair.

项目摘要 该提案的总体目标是开发和评估一组多参数定量MRI（QMRI） 监视与创伤性周围神经损伤（TPNI）和 随后的手术修复 最近的军事任务已经指出了TPNI发病率的增加。 从穿透性损伤，压碎，伸展和缺血的肢体到四肢的创伤。 局限性：i）无法敏锐地识别需要手术的伤害（例如，神经撕裂） 无法在肌肉重新传播之前检测到神经失败，或者您需要几个月的时间或取决于 由于这些限制，需要医生 从患者病史和身体检查中获得。 永久性电动机/感觉丢失。 创伤后的体内神经微观结构的定量表征和恢复过程 （即，在肌肉重新介绍之前），我们建议开发和评估QMRI技术 成功，这些策略可以通过i）确定需要手术的患者和II 识别出比当前技术的手术失败，甚至指导了QMRI 将开发和评估方法作为神经恢复的潜在生物标志物，通过您的人类研究 前臂和腕部的中位数/尺神经。 （AIM 1）。 高分辨率成像和脂肪的影响。 优化QMRI方法来评估继承的神经病。 并利用定量磁化转移和扩散成像来调节沃勒式变性和 受伤/修复后的轴突生长，我们已经表明炎症混淆了 基于扩散的神经恢复的评估 说明炎症的影响。 在各种偏僻的神经损伤患者中，QMRI识别伤害的能力 需要手术。我们还将在手术后进行纵向研究（目标3） QMRI监测神经再生，结果与EMG/NCS和功能相比（例如，握力强度）。 最后，我们将探索MRI方法以监测TPNI对骨骼肌肉的下游影响 当检测到未能进行维修失败时，信息可能会改善未来的复活手术建议。 具体而言，我们将测量由您支配的肌肉中的T2/脂肪分数（急性/慢性神经膜的报道） 中位/尺神经（例如，手的肌肉）评估神经修复后的生存力。