摘要目的探讨术中肌电监测在累及第四脑室底面肿瘤切除术中的应用及影响因素。方法南方医科大学南方医院神经外科自2007年1月至2010年12月在后组颅神经肌电监测下完成累及第四脑室底面肿瘤切除术32例，其中髓母细胞瘤11例，第四脑室室管膜瘤9例，脑干海绵状血管瘤6例，脑干起源外生性胶质瘤4例，脑干背侧血管网状细胞瘤2例。分析术中肌电监测对手术效果的影响及其干扰因素。 结果 本组肿瘤全切除21例，次全切除9例，大部切除2例；无后组脑神经功能障碍9例，轻度后组颅神经损伤18例，中度后组颅神经损伤5例，无严重损伤者。肌电监测结果的干扰因素主要包括双极电凝产生的外泻电流、肌松药物的过多使用、麻醉深度的改变、以及患者体温、冲洗盐水温度、血压急剧变化等。 结论术中肌电监测可以为累及第四脑底面肿瘤切除术中颅神经核团的位置及功能保护提供客观依据。

abstractsObjective To analyze the protective role of intraoperative EMG monitoring in surgical removal of tumors related to the floor of the fourth ventricle and its influencing factors.Methods Intraoperative EMG monitoring was performed during the surgical removal of 32 patients with brain tumor, admitted to our hospital from January 2007 to December 2010; among these 32patients, 11 was conformed as having medulloblastoma, 9 ependymoma, 6 brain stem cavernous hemangioma, 4 brain stem exogenous glioma and 2 hemangioblastoma of the dorsal brain stem. The influencing factors of intraoperative EMG monitoring and the possible damage of cranial nerve nuclei caused by these surgical procedures were analyzed.Results Twenty-one patients enjoyed total removal, 9 sub-total removal and 2 partial removal. Good function protection of patient's posterior cranial nerves was noted in 9 patients, mild impairment in 18 patients, and moderate dysfunction in 5 patients.The influencing factors of EMG monitoring included leaking electric current caused by bipolar coagulation, excessive use of muscle relaxant drugs, changes in depth of anesthesia, and rapid changes of patient′s temperature, saline temperature and blood pressure. Conclusion The intraoperative EMG monitoring can provide evidence about the location of the cranial motor nuclei during the surgical removal of the tumor related to the floor of the fourth ventricle and the function protection of patient’s posterior cranial nerves.