股外侧皮神经炎的电流感觉阈值和体感诱发电位测定

Study on the current perception threshold and somatosensory evoked potential of meralgia paresthetica

目的探讨股外侧皮神经炎的神经纤维受累类型。方法选择临床确诊股外侧皮神经炎患者40例,平均年龄(55.8±14.6)岁。病程为(8d~8年)。麻木感25例,刺痛10例,皮肤叙述不清不适感5例。查体32例患者在大腿前外侧2/3区域有感觉过敏或减退。对全部患者进行电流感觉阈值(CPT)测定,分别记录患侧及健侧在2000 Hz、250 Hz、5 Hz不同频率刺激股外侧皮神经的电流感觉阈值,比较双侧阈值的差别。并对所有患者行双侧股外侧皮神经体感诱发电位(SEP)检查。结果患侧股外侧皮神经2000 Hz、250 Hz、5 Hz刺激的阈值分别为309±27、84±11、70±7,健侧CPT值为188±12、57±4、44±3。三个频率刺激性的患侧和健侧股外侧皮神经阈值差异均有统计学意义。40例患者健侧股外侧皮神经SEP均正常引出,潜伏期(35.21±4.15)ms,患侧14例SEP正常,SEP的平均潜伏期为(36.42±3.28)ms,患侧26例异常,其中22例潜伏期明显延长,平均潜伏期(43.09±5.32)ms,波形未肯定引出2例,潜伏期正常但波幅较对侧明显减低大于50%2例。CPT的诊断灵敏度92.5%,SEP诊断灵敏度65%。结论股外侧皮神经炎患者存在明确的股外侧皮神经损害,主要累及包括粗有髓鞘纤维在内的大纤维和由细有髓鞘纤维及无髓鞘纤维组成的小纤维。推荐将CPT用于股外侧皮神经炎的检查。

Objective To explore the damage of nerve fiber in patients with meralgia paresthetica.Methods There were forty patients with meralgia paresthetica.The average age was 55.8±14.6 years.The course of disease was 8 days to 8 years.There were 25 cases of numbness,10 cases of tingling and 5 cases of indistinct skin description.32 patients had hypoesthesia in 2/3 area of anterolateral thigh.The current perception threshold(CPT)was measured and recorded in the lateral femoral cutaneous nerve by 2000 Hz,250 Hz and 5 Hz different frequency stimulation.The CPT datas were compared.SEP examination of bilateral lateral femoral cutaneous nerve was performed in all patients Results The CPT of lateral femoral cutaneous nerve respectively was 309±27,84±11,70±7 by 2000 Hz,250 Hz and 5 Hz stimulation on diseased side,and respectively 188±12,57±4,44±3 on asymptomatic side.There were significant difference(P<0.05)by 2000 Hz,250 Hz,5 Hz.In 40 patients,the SEP of the lateral femoral cutaneous nerve in the healthy side was normal,the latency was 35.21±4.15 ms.The SEP of 14 patients was normal in the affected side,the average latency of SEP was 36.42±3.28 ms.26 patients were abnormal in the affected side,the latency of 22 patients was significantly prolonged,the average latency was 43.09±5.32 ms,the waveform was not definitely drawn out in 2 patients,the latency was normal but the amplitude was significantly reduced by more than 50%compared with the opposite side in 2 patients.The sensitivity of CPT and SEP was 92.5%and 65%respectively.Conclusion Meralgia paresthetica exist nerve damage,involving myelinated fibers and unmyelinated fiber.CPT is recommended for the examination of meralgia paresthetica.