摘要：

目的 对吸食笑气所致脊髓亚急性联合变性患者的临床与影像学特点进行初步分析。方法与结果 2例患者分别于吸食笑气后5和19个月发生脊髓亚急性联合变性，以四肢麻木、无力为首发症状并逐渐加重。神经传导检测提示神经传导速度减慢、波幅降低；MRI显示颈髓后索呈“倒V”形长T₂ 信号影。停止吸食笑气并以B族维生素营养神经治疗后症状逐渐改善。结论 吸食笑气可导致神经系统损害，表现为脊髓亚急性联合变性，治疗原则为停止吸食笑气并甲钴胺替代治疗。

关键词:  脊髓亚急性联合变性, 氧化亚氮, 维生素B12

Abstract:

Objective To summarize the clinical manifestations and image features of subacute combined degeneration of the spinal cord (SCD) caused by inhalation of nitrous oxide (laughing gas). Methods and Results SCD was happened in two patients who took in nitrous oxide for 5 and 19 months, with numbness and weakness of limbs as the first symptoms and the symptoms gradually got worse. The nerve conduction test showed that the nerve conduction velocity (NCV) was slow down and the amplitude was decreased. MRI showed "inverted V" in the posterior cord of cervical spinal cord on T₂ WI. After stopped taking nitrous oxide and treated with vitamin B, the symptoms gradually alleviated. Conclusions Inhalation of nitrous oxide can cause neurological damage, which can be manifested as SCD. Stopping the inhalation of nitrous oxide and using mecobalamin are the key of the treatment.

Key words: Subacute combined degeneration, Nitrous oxide, Vitamin B12