乳突后小骨窗开颅骨片复位显微手术切除大型桥小脑角肿瘤

目的 探讨大型桥小脑角肿瘤经乳突后小骨窗开颅、骨片复位的手术方法 及其治疗效果.方法 18例大型桥小脑角肿瘤(听神经鞘瘤13例,脑膜瘤3例,胆脂瘤2例)均采用单侧乳突后小骨窗开颅,应用显微神经外科技术进行肿瘤切除,必要时磨开内听道,术中行脑干听觉诱发电位(BAEP)、体感诱发电位(SEP)和面神经功能监测,肿瘤切除后严密缝合硬脑膜,骨片复位.结果 肿瘤全切除17例、次全切除1例.全组患者的面神经均得到了解剖保留.无手术死亡.术后复查MRI示17例肿瘤全切除者未见有肿瘤残留,1例听神经鞘瘤行次全切除者于内听道内可见少许肿瘤组织残留,术后3个月行伽玛刀治疗.术后有10例遗留轻度面瘫(口角稍有歪斜,眼睑闭合良好),均为大型听神经鞘瘤患者,余患者无脑神经功能障碍,恢复良好.结论乳突后小骨窗开颅术适用于不同大小的桥小脑角肿瘤,严格按显微神经外科技术操作,结合术中BAEP,SEP和面神经功能监测,均可做到肿瘤全切除,并能有效地保护肿瘤周围的重要神经结构及其功能.严密缝合硬脑膜和骨片复位可消除局部皮下积液.

Microsurgical excision of large cerebellopontine angle tumors using retromastoid small craniotomy with bone flap replacement

Objective To evaluate the microsurgical methods and the outcomes of retromastoid small craniotomy with bone flap replace for the treatment of large cerebellopontine angle tumors.Methods Eighteen cases of large cerebellopontine angle tumors(13acoustic neurinoma,3 meningioma and 2 epidermoid)were excised with microneurosurgery through unilateral retromastoid small craniotomy.The internal auditory meatus was drilled open if necessary.BAEP,SEP and facial nerve function were monitored during operation.The dura mater was sutured tightly and bone flap was replaced after the tumor removal.Results By using microneurosurgical techniques,tumors were totally resected in 17 cases and subtotally resected in 1 case.Facial nerves were anatomically preserved in all patients.No one died from surgery.All the patients received examination of MRI after operation.MRI revealed no residual tumor in 17 totally-resected patients,and only slight residual tumor tissues in the internal auditory meatus in 1 subtotally-resected patient.This patient received gamma knife therapy 3 months after surgery.Ten acoustic neurinoma patients appeared minor facial palsy after surgery.Others recovered well.Conclusion Unilateral retromastoid small craniotomy is suitable for all sizes of cerebellopontine angle tumors.Tumors can be completely removed by microneurosurgical techniques under the monitoring of BAEP,SEP and facial nerve function.The internal auditory meatus may be drilled open if necessary.The surrounding structures of cerebellopotine angle area and their functions can also be preserved.It may effectively eliminate the local CSF accumulation by tight suturing of the dura mater and replacement of bone flap.