继发面肌痉挛的显微手术治疗

Microsurgical treatment for hemifacial spasm due to tumors

目的探讨因肿瘤继发面肌痉挛（HFS）的临床特征和显微手术治疗的要点。方法回顾性分析1984年10月至2007年3月间作者采用显微手术治疗的小脑脑桥角肿瘤继发的HFS48例的临床资料，并对其中41例进行长期随访。结果肿瘤大小在1．5～5cm之间，均对面神经出脑干区（REZ）造成不同程度的压迫。肿瘤全切除43例，近全切除3例，部分切除2例。37例（77％）在切除肿瘤后见动脉血管和肿瘤共同压迫面神经REZ，故再以Teflon棉对REZ进行显微血管减压。肿瘤类型为表皮样囊肿37例、脑膜瘤4例、听神经瘤2例、舌咽神经鞘瘤3例及迷走神经鞘瘤2例。41例随访时间4-216个月。HFS症状消失38例，有效2例，复发1例。术后永久并发症8例。结论除部分表皮样囊肿可以直接压迫面神经导致面肌痉挛外，其他多数肿瘤继发面肌痉挛均由肿瘤和血管共同作用所致。在切除肿瘤后对“责任血管”的探查和有效减压是保证手术疗效的关键。术前影像学检查有助于判定面肌痉挛是否由肿瘤继发。

Objective To discuss the clinical features of hemifacial spasm （ HFS ）due to tumors and the key points of microsurgical process to treat it. Methods The clinical data of a series of 48 patients with HFS due to cerebellopontine angle tumors surgically treated by the authors from Oct. 1984 to Mar. 2007 were reviewed retrospectively, and 41 cases of them had been followed-up for a long period. Results The tumors were found about 1.5cm to 5cm in diameter, and compressed the root exit zoon of the facial nerve in different extent. The tumors were totally resected in 43 patients, subtotally resected in 3 patients, and partially resected in 2 patients. After resecting the tumors the vascular were found compress the REZ accompanied with the tumor in 37 cases （77%）, so it was push away from the REZ and fixed by Teflon. Intraoperative find and postoperative pathological examinnation disclosed the tumors as follows： epidermoid cysts in 37 cases, meningiomas in 4 cases, Schwannomas of the Ⅷ, Ⅸ and Ⅹ cranial nerve in 2,3 ,and 2 cases respectively. 41 cases had been followed-up for 4 to 216 months. The hemifacial spasm disappeared in 38 cases, improved in 2 case, and recurred in I case. 8 patients suffered from tinnitus/decreased hearing ability and light hemifacial palsy respectively. Conclusions Most HFS secondery to CPA tumors are caused by compression at the REZ of facial nerve by tumors and vasculars, except for some HFS may due to epidermiod cysts only. The key points to success of the operation are exploring the REZ and decompression it after removing the tumor. Preoperative neuroimaging study conduce to judge whether HFS due to tumor or not.