平山病颈椎侧位X线及过屈位MRI表现

目的：研究平山病在颈椎过屈位MRI及颈椎X线侧位片的影像学表现。方法：对23例平山病患者和12例健康志愿者进行过屈位MRI扫描，18例平山病患者颈椎侧位X线片，总结影像学特点。结果：①病例组相邻两椎体后缘角度总体比较有差异，AC5－6最大。②病例组23例（100％）均出现低位颈髓的萎缩。③病例组23例（100％）出现低位脊髓变扁。④脊髓受累分布，C6 23例，C5 18例，C7 11例，C4 1例。⑤C6水平颈髓前后径与对照组相比明显变窄。⑥病例组14例（61％）出现低位颈椎椎管内硬膜后方T2WI异常信号。⑦颈椎曲度变直8例（44％），反弓7例（39％），前凸3例（17％）。结论：颈椎过屈位MRI对诊断平山病有重要意义，颈椎侧位X线曲度异常对平山病有辅助诊断价值。

Imaging features of Hirayama disease on fully flexed position cervical MRI and lateral cervical plain film

Objective： To explore the imaging features of Hirayama disease on fully flexed cervical spine on MRI and lat- eral cervical plain X-ray film. Materials and Methods： MRI examinations in fully flexed neck were performed on 23 cases of Hirayama disease and 12 normal control subjects. Lateral cervical plain films were performed on 18 eases of Hirayama disease. We smnmarized the imaging features of Hirayama disease. Results： （1）For the angles, there were difl＇erence in total comparison（F=1l.22, P〈0.05）. AC5-6 was the largest. （2）23 eases（100%） in the patient group had localized lower cervical cord atrophy. （3）23 cases （100%） in the patient group had loealized lower cervical cord flattening. （4）The levels of invloved cervical cords were localized in C6（23 eases）, C5（18 cases）,C7（11 cases） and C4（1 ease）. （5）The anterior-posterior diameter of the cervical cord showed significant differenee between patients and controls（t=-10.1, P〈0.01）. （6）14 cases （61%） nf patients had erescent-shaped high-intensity mass in the posterior epidural space. （7）The curvature of the cervieal spine was lordotic （3 eases 17%）, straight （8 cases 44%） and kyphofie （7 cases 39%）. Conclusion： Cervieal MRI with fully flexed position has significant values on clinical diagnosis of Hirayama disease. Lateral cervical plain film shows values on the anxiliary diagnosis and sereening of Hirayama disease.