脊髓空洞症10例患者皮肤感觉阈值的测定

Evaluation of neuroselective current perception threshold in 10 patients with syringomyelia

目的 研究选择性神经诊断刺激器在 10例脊髓空洞症患者中的特点和临床意义。方法 对 10例 (男 6例 ,女 4例 )经病史、临床表现和脊髓MRI检查证实的脊髓空洞症患者在双侧的拇指 (C6皮节 )和小指 (C8皮节 )进行了不同频率 (5、2 5 0和 2 0 0 0Hz)皮肤感觉阈值 (CPT)的测定 ,并与年龄匹配的健康人对照。结果 患者组C6和C8皮节对 5和 2 5 0Hz刺激感觉阈值与健康对照组比较 ,差异有非常显著意义 (P <0 .0 1) ,而 2 0 0 0Hz刺激两组之间差异无显著意义。其中 2例临床上有明显的触觉和音叉震动觉减低 ,MRI显示空洞影响脊髓前角和后角 ,2 0 0 0Hz刺激CPT阈值也有明显的增高 (C6和C8刺激CPT阈值分别为 5 32和 718)。不同频率刺激CPT的异常率是不同的 ,5Hz刺激CPT的异常率最高 (C6和C8刺激分别为 5 5 .0 %和 70 .0 % ) ,2 0 0 0Hz刺激的阳性率最低 (C6和C8刺激分别为 15 .0 %和 2 3.5 % )。结论 通过对 10例不同程度脊髓空洞症的研究 ,进一步证明了不同刺激频率CPT的测定可评价不同感觉神经的功能 ,较客观地对不同直径的感觉纤维进行定量测定。

Objective To investigate the changes of neuroselective current perception threshold (CPT) in 10 patients with syringomyelia. Methods Different frequencies (5, 250 and 2 000 Hz) CPT were measured in 10 patients (male 6,female 4) who were diagnosed by history, clinical features and spinal MRI in comparison with 10 age-matched normal controls,by using the first digit (C6 dermotome) and the fifth digit (C8 dermotome) bilaterally. Results It was found that there was a significant different percentage of abnormal CPT between patients and controls at 5 Hz and 250 Hz stimuli( P <0.01)but no significance by using 2 000 Hz. In two patients with severe impairment of touch and vibration sensation and with big cavitations involved in anterior horn and posterior horn, CPT values were also abnormal at 2 000 Hz (532 at C6 and 718 at C8 respectively). It also showed that the highest percentages of abnormal CPT were 55.0% (C6) and 70.0% (C8) at 5 Hz, on contrast to those at 2 000 Hz (15.0% at C6 and 23.5% at C8). Conclusion It is suggested that the CPT at different frequencies might be used to evaluate the function of the different sensory nevers and to quantitate the sensory nerves at different diameters objectively.