Medical Imaging of Peripheral Nerve Injury and Repair

周围神经损伤是一种衰弱的后果，既有四肢创伤性损伤 士兵，以及脊髓损伤(SCI)后的次要后果。同样具有毁灭性的是，对于这两位老兵来说 和普通人群，是指周围组织切除过程中的神经损伤、疾病或医源性损伤。 从神经损伤中恢复功能往往是不完整的，导致运动功能受损，感觉丧失， 和痛苦。慢性神经损伤的恢复尤其差，这可能是由于未修复的神经或 来自延迟的或失败的初级修复。治疗神经损伤的一个主要挑战是目前缺乏有效的 方法对神经进行医学成像。因此，外科医生无法准确地评估其程度 神经损伤，以知情和数据驱动的方式计划手术干预，或评估 神经修复早期时间点，预测远期恢复。 我们开发了神经成像的创新量化策略，克服了挑战 是由神经的复杂结构和结构创造的。我们的方法使用了两个广泛部署的 临床形式、超声(US)和磁共振成像(MRI)。我们的成像方法是 强劲的初步数据表明，定量超声(QUS)和磁共振成像(QMRI)是强大的 以及临床上可行的高分辨率和高分辨率监测神经结构和组成的策略 敏感度。这些方法还旨在为生物变化提供非侵入性替代品， 发生在神经退化和再生期间，但不能在患者身上进行评估。要建立 在临床环境下，QUS和QMRI在评估神经结构和成分方面的有效性和实用性，我们将 在大鼠(目标1)和人类(目标2)急性和慢性神经损伤模型中解决以下特定目标： 1)测试定量超声和磁共振成像技术在评估神经肌肉形态方面的有效性 急、慢性模型大鼠周围神经退变及修复过程中的成分变化 坐骨神经损伤。2)探讨定量超声和磁共振成像技术在临床评估中的作用 人正中神经和尺神经急、慢性模型的神经肌肉形态和组成 紧接手术修复前的损伤。 我们的方法有可能改变神经损伤的诊断和治疗。即刻临床 影响包括：(I)关于决定是否进行神经修复或神经转移手术的客观指导； (2)预测和监测神经修复的效果；(3)指导术后康复方案。这 这项工作还将为一项前瞻性研究奠定基础，在该研究中，成像策略将被部署为预后 预测神经修复后神经肌肉恢复效果的工具，以改善治疗 退伍军人和普通人群中神经损伤的风险。更广泛地说，我们的神经成像策略将有助于 诊断和预测更广泛的神经疾病和神经疾病的神经结构和损伤。

Peripheral nerve damage is a debilitating consequence of both traumatic injury to the extremities of soldiers, and a secondary outcome following spinal cord injury (SCI). Equally devastating, for both the Veteran and general population, is nerve damage during excision of surrounding tissue, disease, or iatrogenic injury. Functional recovery from nerve damage is often incomplete, resulting in impaired motor function, sensory loss, and pain. Recovery is especially poor for chronic nerve injuries, which can result from unrepaired nerves or from delayed or failed primary repair. A major challenge in treating nerve injury is the current lack of effective methods to medically image nerves. As a consequence, surgeons are unable to accurately assess the extent of nerve injury, plan surgical intervention in an informed and data-driven manner, or assess the success of nerve repair at early time points, to predict long-term recovery. We have developed innovative quantitative strategies for nerve imaging, which overcome challenges created by the complex structure and architecture of nerves. Our approach employs two widely deployed clinical modalities, ultrasound (US) and magnetic resonance imaging (MRI). Our imaging approach is motivated by strong preliminary data demonstrating that quantitative US (qUS) and MRI (qMRI) are powerful and clinically feasible strategies for monitoring nerve structure and composition at high-resolution and with high sensitivity. These approaches are also intended to provide non-invasive surrogates for biological changes that occur during nerve degeneration and regeneration, but which cannot be evaluated in patients. To establish the validity and utility of qUS and qMRI in evaluating nerve structure and composition in a clinical setting, we will address the following specific aims in rat (Aim 1) and human (Aim 2) models of acute and chronic nerve injury: 1) To test the efficacy of quantitative US and MR imaging strategies in assessing neuromuscular morphology and composition during peripheral nerve degeneration and following repair of acute and chronic models of rat sciatic nerve injury. 2) To test the clinical efficacy of quantitative US and MR imaging strategies in assessing neuromuscular morphology and composition in acute and chronic models of human median and ulnar nerve injury immediately prior to surgical repair. Our approach has the potential to transform the diagnosis and treatment of nerve injury. Immediate clinical impacts include: (i) objective guidance on deciding whether to perform nerve repair or nerve transfer surgery; (ii) predicting and monitoring the efficacy of nerve repair; (iii) guidance for post-op rehabilitation protocols. This work will also set the stage for a prospective study in which imaging strategies will be deployed as prognostic tools for predicting the efficacy of neuromuscular recovery following nerve repair, towards improved treatment of nerve injury in Veteran and general populations. More broadly, our nerve imaging strategy will aid in the diagnosis and prediction of nerve structure and damage for a wider array of neuropathies and nerve diseases.