面肌痉挛显微血管减压术中脑干听觉诱发电位监测的应用

目的 研究脑干听觉诱发电位(BAEP)监测在显微血管减压术(MVD)治疗面肌痉挛手术中的应用.方法 回顾性分析90例面肌痉挛患者在MVD术中进行BAEP监测的临床资料.结果 MVD手术操作过程均可引起BAEP改变,包括:BAEP的Ⅰ、Ⅲ、Ⅴ波绝对潜伏期明显延长(P＜0.01),Ⅰ～Ⅲ、Ⅲ～Ⅴ、Ⅰ～Ⅴ波间期明显延长(P＜0.01),Ⅲ波、Ⅴ波波幅明显降低(P＜0.01);有16例术中Ⅴ波绝对潜伏期延长超过1ms,Ⅰ波波幅也有明显降低(P＜0.01),但术后无听力障碍;手术结束时Ⅲ～Ⅴ波间期及16例的Ⅰ、Ⅴ波波幅恢复较快.2例术后患侧听力丧失的患者中,1例术中Ⅴ波波幅逐渐降低至消失,另1例术中未监测到Ⅴ波波形.结论 MVD手术操作过程均可引起BAEP改变;Ⅴ波绝对潜伏期延迟超过1ms者相对多见,但无听力受损;Ⅴ波波幅下降程度可为术中神经功能受损提供客观指标,以采取相应措施减少听力并发症的发生.

Application of brain stem evoked potential monitoring in microvascular decompression for hemifacial spasm

Objective To study the application of brain stem evoked potential(BAEP) monitoring in microvascular decompression (MVD) for treatment of hemifacial spasm (HFS).Method The clinical data of 90 patients of HFS treated by MVD under introperative monitoring of BAEP were evaluated retrospectively.Results Changes of BAEP were monitored in all MVD procedures.The changes included elongation of obsolute latency of Ⅰ ,Ⅲ,Ⅴ waves(P＜0.01); elongation of inter-wave period of Ⅰ～Ⅲ,Ⅲ～Ⅴ,Ⅰ～Ⅴ waves (P＜0.01); decrease of the amplitude of Ⅲ,Ⅴ waves(P＜0.01).But there was no change in the amplitude of Ⅰ wave.The elongation of the obsolute latency of Ⅴ wave (≥ 1 ms) and decrease of the amplitude of Ⅰ waves (P＜0.01) were observed in 16 patients,but there was no auditory dysfunction in these patients.The inter-wave periods of Ⅲ～Ⅴ waves of all patients and the amplitudes of Ⅰ,Ⅴ waves of those 16 patients were returned to normal levels quickly at the end of operation.There were 2 patients who lost their unilateral auditory function: the amplitude of Ⅴ wave was decreased to zero in 1 patient and there was no detected Ⅴ wave in 1 patient.Conclusion Changes of BAEP chould be monitored in all MVD procedures.The elongation of the obsolute latency of Ⅴ wave (≥1 ms) are common but there is no concomitant auditory dysfunction.The significant decrease of the amplitude of Ⅴ wave is an objective guide line for auditory dysfunction.Acording to introperative monitoring,alternative operative strategy chould decrease the incidence of auditory dysfunction.