经扩大乙状窦后入路手术切除大型岩斜区脑膜瘤

Extended retrosigmoid approach for surgery of large petroclival meningiomas.

目的探讨扩大乙状窦后入路在显微手术切除大型岩斜区脑膜瘤中的应用。方法采用扩大乙状窦后入路的手术方式，显微切除大型岩斜区脑膜瘤6例，肿瘤最大直径3．4-6．7cm,平均4．5cm，术中切除枕骨和乳突，完全显露横窦和乙状窦，通过悬吊硬脑膜将它们分别向上方和前方牵开，有效地减少了两个粗大的静脉窦对小脑幕下方和岩骨背面的遮挡，手术视野明显增大，能够充分暴露小脑幕和岩骨背面。结果本组肿瘤全切除3例，次全切除2例，大部切除1例，无手术死亡，神经功能较术前改善1例，与术前相同3例，2例出现新增脑神经损害，未发生脑脊液漏和切口感染。术后随访6-58个月，所有病例MRI复查未见肿瘤复发或增大。结论扩大乙状窦后人路具有增加暴露范围、扩大手术视角、早期阻断肿瘤血液供应、避免过度牵拉小脑、改善深部结构的显露、有利于保护脑神经和重要血管等优点。

Objective To evaluate the extended retrosigmoid approach for surgery of large petroclival meningiomas. Methods We retrospectively analyzed our experience in 6 patients with large petroclival meningiomas treated by extended retrosigmoid approach. The maximum diameter of tumors ranged from 3.4 to 6. 7 cm （ mean, 4. 5 cm）. The sigmoid sinus and the transverse sinus were thoroughly exposed with the bone removal including mastoid and occipital bones. The stay sutures of the dura flaps were performed to pull the sigmoid sinus anteriorly and the transverse sinus upward to widen the opening into the infratentorial space and the posterior surface of the petrous bone. Results Gross total resection of the tumors was achieved in 3 cases, subtotal resection in 2 cases and partial resection in 1 case. No patients died. The neurological deficits improvement was found in 1 case, unchanged in 3 cases, and 2 patients were found to have new cranial nerves palsy. There was no CSF leakage and infections after operations. There was no tumor recurrence or growth by MRI scanning during the follow-up period of 6 to 58 months in all patients. Conclusion The extended retrosigmoid approach can enhance the surgical exposure, enlarge the operative view, cut the blood supply of tumor earlier, and avoid the excessive retraction on cerebellum, as well as facilitate the protection of these vital cranial nerves and vessels around brain stem.