华勒变性(WD)为神经受损后,神经远端的髓鞘分解消失、轴突发生坏死以及神经鞘膜增生等细胞吞噬和蜕变的过程~([1])。WD可发生于中枢神经系统及周围神经系统,常以累及椎体束最为多见[2]。现临床,检查判断神经损伤程度主要为神经电生理检查,其对神经近端病变及完全损伤的评估缺乏特异性及敏感性。本研究通过分析脑梗死累及单侧锥体束病变继发华勒变性患者MRI及DTI图像病灶信号特征及分布 Waller degeneration (WD) is a process of phagocytosis and metamorphosis of neurons after the nerve damage, disappearance of the distal myelin sheath, axonal necrosis and nerve sheath hyperplasia and so on ([1]). WD can occur in the central nervous system and peripheral nervous system, often involving the most common vertebral bundle [2]. Clinical, examination to determine the degree of nerve damage is mainly neuroelectrophysiology, its assessment of proximal nerve lesions and complete lack of specificity and sensitivity. In this study, we analyzed the characteristics and distribution of MRI and DTI lesion signals in patients with Fetal Lesion affected by unilateral pyramidal tract lesions