平山病的MRI表现及临床诊断价值

MRI Manifestation of Hirayama Disease and Its Diagnostic Value

目的研究和总结平山病患者颈椎中立位和前屈位MRI的特点,探讨其对平山病诊断的价值。方法分析17例平山病患者颈椎中立位MRI低位颈髓形态、颈椎曲线、失连接(LOA)、脊髓内T2WI高信号;前屈位硬脊膜囊后壁前移、硬膜外间隙增宽伴流空信号等征象。结果颈椎中立位MRI低位颈髓萎缩、变扁10例(58.8%),颈椎曲线异常14例(82.4%),LOA征17例(100%),脊髓T2WI高信号影4例(23.5%);前屈位MRI硬膜囊后壁前移,低位颈髓受压17例(100%),硬膜外间隙增宽17例(100%),伴流空信号影16例(94.1%)。结论颈椎前屈位硬脊膜囊后壁前移、硬膜外间隙增宽伴流空信号、中立位LOA等征象具有明显的特征性,有很高的诊断价值。

Objective To study and summarize MRI manifestations of cervical spine obtained at flexion position and neutral position in patients with Hirayama disease, and to discuss the clinical value of these signs in making diagnosis. Methods A total of 17 patients with Hirayama disease were enrolled in this study. MR scanning was performed in all patients. The shape of lower cervical cord, the cervical curvature, the loss of attachment （LOA） and the intramedullary high signal intensity on T2-weighted images obtained at neutral position were analyzed. The anterior shifting of posterior dura matter, the widening of epidural space and the flow void signals demonstrated at flexion position were recorded. The results were analyzed. Results Neutral position cervical MR images showed that the lower cervical cord was atrophied and flat- tened in 10 cases （58.8%） , abnormal cervical curvature was found in 14 cases （82.4%）, and LOA was seen in all 17 cases （100%）. Intramedullary high signal intensity on T2-weighted MR images was detected in 4 cases （23.5%）. Flex- ion position cervical MR images revealed that anterior shifting of posterior dura matter with lower cervical cord oppression as well as widening of epidural space could be found in all 17 cases （ 100% ）, and flow void signals in epidural space could be seen in 16 cases （94.1%）. Conclusion Several cervical MRI signs, such as anterior shifting of posterior dura matter, widening of epidural space and flow void signals in flexion position, LOA in neutral position, etc. are of great characteristics, which are very valuable in diagnosing Hirayama disease.