Imaging Strategies To Improve Diagnosis and Treatment of Entrapment Neuropathy

周围神经是存在于动态生物力学环境中的组织良好的复合组织 由关节运动产生。为了适应机械负荷，神经滑动和伸展 在他们的床上。神经卡压改变了神经的结构，限制了它们的滑动能力， 增加区域变形，最终损害感觉和运动功能。最常见的 退伍军人中的压迫性神经病变是腕管综合征（CTS），一种疾病，其中中位数 神经在腕部受到影响，在腕管内。腕管综合征的治疗方法 一般有效，但3-20%的手术可能需要翻修。鉴于CTS的流行， 对应于相当多的患者。电诊断被认为是金标准， CTS诊断，不确定的结果并不少见，特别是在存在其他重叠 神经病变，如糖尿病性神经病变。 尽管它们可能影响神经病变的进展，但神经结构和生物力学的变化， 仅最低限度地用于诊断或跟踪神经病变，或评估手术治疗的疗效。 这在很大程度上是由于与使用当前技术对神经进行成像相关联的挑战。我们 一个研究小组开发了新的磁共振成像（MRI）和基于超声的成像方法 其允许在高空间分辨率下对比神经的可视化。这些功能允许准确 测量神经生物力学（变形和刚度），以及识别和定量 表征神经内的结构元件。这些方法有望提供一个强大的， 敏感的方法来非侵入性地评估神经病变和手术疗效。 鉴于它的流行，CTS提供了一个理想的测试平台，用于翻译我们的神经成像和图像 将处理技术应用于临床环境。特别是，我们建议使用超声和MRI技术， 评估CTS手术患者正中神经的结构和生物力学。我们的建议 使用多学科方法来解决两个具体目标。我们的第一个目标是优化基于MRI的 正中神经的超声成像方法。我们将使用人体尸体和体内模型， 验证和优化将在临床上使用的成像协议。我们预计，基于MRI的策略将 提供神经的高分辨率和高对比度结构图像，而超声将提供快速的 神经运动学和刚度的评估。我们的第二个目标是研究结构和运动学的变化 腕管综合征患者腕管松解前后正中神经的MRI和超声检查。我们 假设基于MRI成像将检测神经外膜、神经束膜和神经纤维的结构差异 控制和被困神经之间的间隔，超声将检测神经的差异， 手术前后对照神经和卡压神经之间的变形和僵硬。 更广泛地说，我们预计将我们的方法应用于影响退伍军人的其他神经系统疾病。 医疗保健系统，其中神经结构和生物力学可能会改变。其中包括其他 压迫性神经病、糖尿病性神经病和创伤性神经损伤。最终，成功执行 我们提出的研究将能够早期识别神经病变，提供神经病变的非侵入性监测， 这有助于更准确地评估康复和治疗效果。 1

Peripheral nerves are well-organized composite tissues that exist in a dynamic biomechanical environment created by the movement of articulating joints. To accommodate mechanical loads, nerves glide and stretch within their beds. Nerve entrapment alters the structure of nerves, restricts their ability to glide, and excessively increases regional deformation, ultimately impairing sensory and motor function. The most common entrapment neuropathy among Veterans is carpal tunnel syndrome (CTS), a disease in which the median nerve is impinged at the wrist, within the carpal tunnel. Surgical treatment of carpal tunnel syndrome is generally effective, but revision may be required for 3-20% of surgeries. Given the prevalence of CTS, this corresponds to a substantial number of patients. Electrodiagnostics are considered to be the gold standard for CTS diagnosis, inconclusive outcomes are not uncommon, especially in the presence of other overlying neuropathies, such as diabetic neuropathy. Despite their likely influence on neuropathic progression, nerve structural and biomechanical changes have been used only minimally to diagnose or track neuropathy, or to assess the efficacy of surgical management. This is in large part due to the challenges associated with imaging nerves using current techniques. Our research team has developed new magnetic resonance imaging (MRI) and ultrasound-based imaging methods that allow the visualization of nerves at high spatial resolution on contrast. These capabilities allow accurate measurement of nerve biomechanics (deformation and stiffness), and also identification and quantitative characterization of structural elements within nerves. These methods are expected to provide a powerful and sensitive approach to non-invasively assess neuropathy and surgical efficacy. Given its prevalence, CTS provides an ideal test-bed for translating our nerve imaging and image processing techniques to a clinical setting. In particular, we propose to use ultrasound and MRI techniques to evaluate structure and biomechanics of median nerves in patients requiring surgery for CTS. Our proposal uses a multi-disciplinary approach to address two specific aims. Our first aim is to optimize MRI-based and ultrasound imaging methodology in median nerves. We will use human cadaveric and in vivo models to validate and optimize imaging protocols that will be used clinically. We expect that MRI-based strategies will provide high resolution and high contrast structural images of nerves, while ultrasound will provide rapid assessment of nerve kinematics and stiffness. Our second aim is to examine structural and kinematic changes of median nerves in patients with CTS, before and after carpal tunnel release, using MRI and ultrasound. We hypothesize that MRI-based imaging will detect structural differences in epineurial, perineurial, and nerve fiber compartments between control and entrapped nerves, and ultrasound will detect differences in nerve deformation and stiffness among control nerves and entrapped nerves before and after surgery. More broadly, we anticipate applying our approach to other neurological conditions that impact the Veteran healthcare system, in which nerve structure and biomechanics may be altered. These include other entrapment neuropathies, diabetic neuropathy, and traumatic nerve injury. Ultimately, successful execution of our proposed study will enable earlier recognition of neuropathy, provide noninvasive monitoring of neuropathic progression, and facilitate more accurate assessment of rehabilitative and therapeutic efficacy. 1