目的 探讨平山病的MR表现及其诊断价值。方法 回顾分析5例临床确诊的平山病患者MR资料。5例患者均行颈椎自然 位和过屈位平扫及增强扫描。所有患者均进行常规生化及脑脊液检查，肌电图检查和肌肉活检。结果 5例患者颈椎 生理曲度均变直，自然体位5例均有低位脊髓萎缩变扁,萎缩的脊髓内有异常信号。屈颈髓位5例可见特征性的颈髓 前移、变平，硬脊膜向前移位，硬膜外腔增宽，4例患者硬膜外腔可见血管流空信号，5例患者在硬脊膜外腔可见强 化的静脉丛。结论 自然位结合过屈位MR平扫+增强检查，对平山病的早期、准确诊断及鉴别诊断具有重要价值。

Objective MR explore Hirayama disease manifestations and diagnostic value. Methods Retrospective analysis of five cases of clinically diagnosed patients Hirayama MR data. Five patients underwent cervical flexion natural position and unenhanced and enhanced scan. All patients underwent routine biochemical and cerebrospinal fluid examination, EMG and muscle biopsy. Results Five patients were seen in cervical lordosis straight, natural position five cases had low spinal atrophy flat, abnormal signal within the spinal cord atrophy. Bit 5 patients with cervical spinal cord flexor visible characteristic of spinal cord forward, flattened, forward displacement of the dura, epidural widened, 4 patients epidural space visible blood flow signals, five patients enhanced visibility in epidural venous plexus. Conclusion Natural position combined flexion MR scan + Enhanced detection, early, accurate diagnosis and differential diagnosis of Hirayama disease is of great value.