基于Sunderland分级的兔坐骨神经损伤的弥散张量成像定量研究

周围神经损伤是临床上常见的严重创伤性疾病之一，其中张力性损伤与挤压伤是常见的致伤原因，且以仍保持神经连续性的Sunderland I-IV级损伤最为常见。受损神经的再生能力强弱及其是否需要手术修复与Sunderland分级密切相关。迄今为止，临床查体、电生理及常规影像学检查均难以可靠地对仍保持连续性的受损神经进行Sunderland分级。弥散张量成像 (DTI)是一种可无创性显示神经组织细微结构变化的功能磁共振成像新技术，能有效评价周围神经轴突退变与再生，在无创性鉴别Sunderland I-IV 级神经损伤方面具有很大的潜力。因此本课题拟利用3.0T磁共振仪DTI序列定量研究兔坐骨神经Sunderland I-IV级张力性及挤压性损伤ADC、FA值及随时间变化规律，探讨兔坐骨神经Sunderland I-IV级损伤及预后与ADC、FA值的相关性，为进一步的临床研究提供理论基础。

Peripheral nerve injuries may result in considerable disability and its incidence increases year by year. Traction injury and crush injury are generally considered to be the most common type of civilian nerve trauma. The majority of these nerve injuries leave the nerve in continuity, with Sunderland classifications of I-IV grades. There is a close relationship between the nerve regeneration and the Sunderland grade. Clinical and electrodiagnostic examinations, and conventional imaging cannot reliably distinguish the Sunderland grades of nerve injury. In such cases, the outlook for spontaneous regeneration and recovery is uncertain. Diffusion tensor imaging (DTI) interrogates the random thermal motion of water molecules within tissues along different axes. It can therefore, be used to exploit the potential of distinct microstructural properties of the peripheral nerves that hinder proton diffusion in some directions and facilitate in other directions. DTI thus allows interrogation into the micro-architecture of the nerves, which is beyond the resolution of anatomic imaging techniques. Thus in order to help predict the Sunderland grade of nerve damage and monitor the process of nerve recovery in acute peripheral nerve injuries, we prospectively evaluate mean FA values and ADCs and the time courses with Sunderland classification in rabbit models of acute nerve traction injury and crush injury.