平山病的MRI表现

MRI features of Hirayama disease

目的认识平山病的MRI表现并探讨其在诊断该病中的价值。方法对8例经临床确诊的平山病患者行颈椎自然位和屈颈位的平扫增强成像,回顾性分析其MRI表现。结果自然位MRI见颈椎生理曲度变直5例,曲度反弓1例,下段脊髓萎缩变细、扁平5例,后脊膜与邻近椎弓失连接4例;全部病例屈颈位MRI均可见硬膜囊后壁向前移位,后硬脊膜外新月形异常信号,此异常信号增强后明显强化,于自然位消失。结论平山病的MRI表现具有一定的特征性。颈椎自然位和屈颈位的平扫增强MR扫描可作为辅助诊断平山病的常规手段。

[Objectives] To recognize the MRI findings of Hirayama disease, and to evaluate its clinical value. [Methods] Eight patients with Hirayama disease confirmed clinically underwent pre and post contrast neutral and flexion position cervical MRI. The MR images were reviewed and analyzed retrospectively. [ Results ] The neutralposition cervical MRI manifestations were as follows： straight cervical curvature in 5 cases, kyphotic cervical curvature in one case, localized lower cervical cord atrophy and flattening in 5 cases, and loss of attachment between the posterior dural sac and subjacent lamina in 4 cases. The anterior shifting of cervical dural sac and posterior epidural crescent-shaped component with flow voids were noted in all eight cases at flexion position. The posterior epidural component enhanced significiantly after intravenous contrast examination and disappeared when the patient returned to a neutral position. [Conclusion] Hirayama disease has some characteristic features on cervical MRI. The pre and post contrast neutral and flexion position cervical MRI can be used as a routine aided method for the diagnosis of Hirayama disease.