Henry Francis P, Wang Yan, Rodriguez Carissa L R, Randolph Mark A, Rust Esther A Z, Winograd Jonathan M, de Boer Johannes F, Park B Hyle
Massachusetts General Hospital Harvard Medical School, Wellman Center for Photomedicine, Boston, Massachusetts 02114, United StatesbMassachusetts General Hospital Harvard Medical School, Plastic Surgery Research Laboratory, No. 15 Parkman Street, WACC 435.
Massachusetts General Hospital Harvard Medical School, Wellman Center for Photomedicine, Boston, Massachusetts 02114, United StatescUniversity of California, Department of Bioengineering, Bourns A247, 900 University Avenue, Riverside, California 92521, Un.
J Biomed Opt. 2015 Apr;20(4):046002. doi: 10.1117/1.JBO.20.4.046002.
Assessing nerve integrity and myelination after injury is necessary to provide insight for treatment strategies aimed at restoring neuromuscular function. Currently, this is largely done with electrical analysis, which lacks direct quantitative information. In vivo optical imaging with sufficient imaging depth and resolution could be used to assess the nerve microarchitecture. In this study, we examine the use of polarization sensitive-optical coherence tomography (PS-OCT) to quantitatively assess the sciatic nerve microenvironment through measurements of birefringence after applying a nerve crush injury in a rat model. Initial loss of function and subsequent recovery were demonstrated by calculating the sciatic function index (SFI). We found that the PS-OCT phase retardation slope, which is proportional to birefringence, increased monotonically with the SFI. Additionally, histomorphometric analysis of the myelin thickness and g-ratio shows that the PS-OCT slope is a good indicator of myelin health and recovery after injury. These results demonstrate that PS-OCT is capable of providing nondestructive and quantitative assessment of nerve health after injury and shows promise for continued use both clinically and experimentally in neuroscience.
评估损伤后的神经完整性和髓鞘形成情况对于为旨在恢复神经肌肉功能的治疗策略提供见解至关重要。目前，这主要通过电分析来完成，而电分析缺乏直接的定量信息。具有足够成像深度和分辨率的体内光学成像可用于评估神经微结构。在本研究中，我们通过在大鼠模型中施加神经挤压伤后测量双折射，研究了偏振敏感光学相干断层扫描（PS-OCT）在定量评估坐骨神经微环境中的应用。通过计算坐骨神经功能指数（SFI）来证明功能的初始丧失和随后的恢复。我们发现，与双折射成正比的PS-OCT相位延迟斜率随SFI单调增加。此外，对髓鞘厚度和g比值的组织形态计量学分析表明，PS-OCT斜率是损伤后髓鞘健康和恢复的良好指标。这些结果表明，PS-OCT能够对损伤后的神经健康进行无损定量评估，并在神经科学的临床和实验应用中显示出持续使用的前景。
