目的 在患有腰椎间盘突出症的 患者中使用磁共振弥散张量成像术(DTI) 对已经发生病变的神经根的作用。方法 对本院65例已经诊断为腰椎间盘突出症的 患者以及65例在本院体检中心筛选的健 康人，进行DTI、T2WI、轴位T2WI以及矢 状位T1WI扫描检查，并监测腰骶神经根 的表观扩散系数值(ADC)以及各向异性分 数值(FA)。结果 65例患者中，两侧神经 根同时病变者15例，仅左侧神经根病变者 20例，仅右侧神经根病变者30例。DTI图 像显示，患者神经根中断或者聚拢，没有 周围分支，神经纤维束面积显著减小，与 正常人差异显著(P<0.05)。而轴位T2WI同 时显示脊神经根病变严重，是椎间盘膨出 或者突出使椎间孔变窄导致的。结论 大 部分患者由于腰椎间盘突出都会导致腰腿 痛以及其他的临床症状，为了给这些症状 的诊断提供参考依据，可以测定FA、ADC 的值，这两个值可以间接反映水分子在神 经根内的运动。而要定量评价神经根的病 变程度，磁共振扩散张量成像会是一个比 较好的选择，它能对神经根采用功能性成 像，对传统的磁共振序列是很好的创新， 有望在利用DTI对神经束的形态以及面积 方面的优势对腰椎间盘突出症的患者的神 经根病变进行诊断。

Objective Toanalyze the effect of magnetic resonance diffusion tensor imaging (DTI) on the role of the pathological changes of nerve root happened on patients with lumbar intervertebral disc protrusion. Methods We selected 65 cases of patients who had been diagnosed with lumbar intervertebral disc protrusion (bulging lumbar or outstanding), and 65 cases of healthy people selected in physical examination center of our hospital. We carried on the DTI, T2WI, axial T2WI and sagittal T1WI scan to monitor the lumbosacral nerve roots in the apparent diffusion coefficient (ADC) valueand anisotropic score value (FA). Results 15 cases had both sides of nerve root lesions,20 cases had left nerve root lesions and 30 cases had right nerve root lesions in 65 cases of patients with lumbar intervertebral disc protrusion. DTI images showed that nerve fiber bundle area of patients with nerve root interrupt or gathering together was significantly reduced and with significant difference(P<0.05). Conclusion In order to obtain an intuitive imaging basis and quantitative numerical values, clinically lumbosacral nerve roots in DTI can be used to get the diagnosis to patients with lumbar disc.The majority of patients with lumbar disc will result in waist, leg pain and other clinical symptoms. ADC values can be used to provide reference basis for the diagnosis of these symptoms and measure the FA. The two values can indirectly reflect the movement of water molecules in the nerve root.To quantitatively evaluate degree of nerve root of pathological changes, magnetic resonance diffusion tensor imaging is a better choice. It can make functional images on nerve root. The traditional. Mri sequen ce is a good innovation, which is expected to use the advantages of morphology of nerve bundle and area of DTI to diagnose the nerve root disease of patients with lumbar intervertebral disc protrusion.