Retrosigmoid approach for vestibular schwannoma surgery: A systematic review of facial nerve functional outcomes
DOI:
https://doi.org/10.20956/csznd236Abstract
Background: Preservation of facial nerve (FN) function is a central goal in vestibular schwannoma (VS) surgery, given its profound impact on patient quality of life. The retrosigmoid (RS) approach is widely employed, but reported outcomes vary across studies, with heterogeneity in patient selection, tumor size, and surgical technique. This systematic review aimed to synthesize published evidence on FN outcomes following RS resection of VS.
Methods: Following PRISMA 2020 guidelines, PubMed, Embase, Scopus, and Web of Science were searched from inception to September 2025. Eligible studies included observational or interventional reports of VS surgery performed via the RS approach that reported postoperative FN function using the House–Brackmann (HB) scale or equivalent. Two reviewers independently screened studies, extracted data, and assessed risk of bias using validated tools for nonrandomized designs.
Results: Seventeen studies published between 2003 and 2025 met inclusion criteria, encompassing a broad spectrum of tumor sizes and patient populations. Postoperative FN outcomes were most often reported as HB grade at early and late follow-up. Across studies, 60–85% of patients achieved good FN function (HB I–II) following RS surgery, with higher preservation rates in small to medium tumors and when intraoperative monitoring was utilized. Comparative studies suggested that RS offered equal or superior FN outcomes compared to translabyrinthine and middle fossa approaches, while also allowing hearing preservation in selected cases. Negative prognostic factors included large tumor size, cystic morphology, and extent of resection, whereas meticulous technique and adjunctive endoscopic assistance were associated with improved results. Reported complications included cerebrospinal fluid leak, headache, and synkinesis. Risk of bias was moderate due to retrospective study designs, small cohorts, and variability in outcome reporting.
Conclusion: The RS approach for VS surgery achieves favorable FN outcomes in the majority of patients, particularly in smaller tumors and when aided by intraoperative monitoring or endoscopic assistance. However, outcomes decline with increasing tumor size and complexity. Current evidence is limited by study heterogeneity and methodological quality, underscoring the need for prospective multicenter trials with standardized FN outcome reporting.
Keywords: vestibular schwannoma, acoustic neuroma, retrosigmoid approach, facial nerve, surgical outcomes
References
1. Gupta, V. K., Thakker, A., & Gupta, K. K. (2020). Vestibular Schwannoma: What We Know and Where We are Heading. Head Neck Pathol, 14(4), 1058-1066. doi:10.1007/s12105-020-01155-x
2. Haider, N., Radi, Q., Ahmad, S., & Mohsen, S. (2025). Unmasking vestibular schwannoma: A series of unusual cases. International Journal of Surgery Case Reports, 131, 111291. doi:https://doi.org/10.1016/j.ijscr.2025.111291
3. Tuan, H. X., Hung, N. D., Khuong, N. H., Duong, Q. T., Dung, L. D., & Duc, N. M. (2023). Vestibular schwannoma with fluid-fluid levels mimicking aneurysm bone cyst. Radiology Case Reports, 18(3), 1079-1083. doi:https://doi.org/10.1016/j.radcr.2022.12.063
4. Leon, J., Lehrer, E. J., Peterson, J., Vallow, L., Ruiz-Garcia, H., Hadley, A., . . . Trifiletti, D. M. (2019). Observation or stereotactic radiosurgery for newly diagnosed vestibular schwannomas: A systematic review and meta-analysis. J Radiosurg SBRT, 6(2), 91-100.
5. Jakubeit, T., Sturtz, S., Sow, D., Groß, W., Mosch, C., Patt, M., . . . Markes, M. (2022). Single-fraction stereotactic radiosurgery versus microsurgical resection for the treatment of vestibular schwannoma: a systematic review and meta-analysis. Systematic Reviews, 11(1), 265. doi:10.1186/s13643-022-02118-9
6. Saraniti, C., & Verro, B. (2024). Reanimation Techniques of Peripheral Facial Paralysis: A Comprehensive Review Focusing on Surgical and Bioengineering Approaches. J Clin Med, 13(20). doi:10.3390/jcm13206124
7. Mengi, E., Orhan Kara, C., Necdet Ardıç, F., Topuz, B., Metin, U., Alptürk, U., . . . Şenol, H. (2024). Comparison of the Reliability of the House- Brackmann, Facial Nerve Grading System 2.0, and Sunnybrook Facial Grading System for the Evaluation of Patients with Peripheral Facial Paralysis. J Int Adv Otol, 20(1), 14-18. doi:10.5152/iao.2024.231162
8. Hostettler, I. C., Jayashankar, N., Bikis, C., Wanderer, S., Nevzati, E., Karuppiah, R., . . . Roethlisberger, M. (2021). Clinical Studies and Pre-clinical Animal Models on Facial Nerve Preservation, Reconstruction, and Regeneration Following Cerebellopontine Angle Tumor Surgery-A Systematic Review and Future Perspectives. Front Bioeng Biotechnol, 9, 659413. doi:10.3389/fbioe.2021.659413
9. Matsushima, K., Kohno, M., Sakamoto, H., Ichimasu, N., & Nakajima, N. (2022). Intraoperative Continuous Neuromonitoring for Vestibular Schwannoma Surgery: Real-Time, Quantitative, and Functional Evaluation. World Neurosurg, 158, 189. doi:10.1016/j.wneu.2021.11.102
10. Matsushima, K., Komune, N., Matsuo, S., & Kohno, M. (2017). Microsurgical and Endoscopic Anatomy for Intradural Temporal Bone Drilling and Applications of the Electromagnetic Navigation System: Various Extensions of the Retrosigmoid Approach. World Neurosurgery, 103, 620-630. doi:https://doi.org/10.1016/j.wneu.2017.04.079
11. Papazian, M., Cottrell, J., Pan, L., Kay-Rivest, E., Friedmann, D., Jethanamest, D., . . . McMenomey, S. (2024). Characterizing Hearing Outcomes Following Treatment of Cerebellopontine Angle Meningiomas. Journal of Neurological Surgery Part B: Skull Base, 0. doi:10.1055/a-2399-0081
12. Daming, C., Yiwen, S., Bin, Z., Yajun, X., Jia, Y., Rui, S., . . . Meiqing, L. (2014). Large vestibular schwannoma resection through the suboccipital retrosigmoid keyhole approach. J Craniofac Surg, 25(2), 463-468. doi:10.1097/scs.0000000000000528
13. Zhao, J., Wang, S., Zhao, X., Cui, H., & Zou, C. (2023). Risk factors of cerebrospinal fluid leakage after neuroendoscopic transsphenoidal pituitary adenoma resection: a systematic review and meta-analysis. Front Endocrinol (Lausanne), 14, 1263308. doi:10.3389/fendo.2023.1263308
14. Milicevic, M., Solari, D., Illic, R., Frio, F., Stanimirovic, A., Savic, D., . . . Grujicic, D. (2020). The Impact of Intraoperative Monitoring on Extent of Resection and Long-Term Neurological Outcomes: A Series of 39 Intramedullary Ependimomas. Turk Neurosurg, 30(2), 252-262. doi:10.5137/1019-5149.Jtn.27471-19.2
15. Page, M. J., McKenzie, J. E., Bossuyt, P. M., Boutron, I., Hoffmann, T. C., Mulrow, C. D., . . . Moher, D. (2021). The PRISMA 2020 statement: an updated guideline for reporting systematic reviews. BMJ, 372, n71. doi:10.1136/bmj.n71
16. Samii, M., Gerganov, V., & Samii, A. (2006). Improved preservation of hearing and facial nerve function in vestibular schwannoma surgery via the retrosigmoid approach in a series of 200 patients. J Neurosurg, 105(4), 527-535. doi:10.3171/jns.2006.105.4.527
17. Kim, K. H., Cho, Y. S., Seol, H. J., Cho, K. R., Choi, J. W., Kong, D. S., . . . Lee, J. I. (2021). Comparison between retrosigmoid and translabyrinthine approaches for large vestibular schwannoma: focus on cerebellar injury and morbidities. Neurosurg Rev, 44(1), 351-361. doi:10.1007/s10143-019-01213-1
18. Ho, S. Y., Hudgens, S., & Wiet, R. J. (2003). Comparison of postoperative facial nerve outcomes between translabyrinthine and retrosigmoid approaches in matched-pair patients. Laryngoscope, 113(11), 2014-2020. doi:10.1097/00005537-200311000-00030
19. Ahmad, R. A., Sivalingam, S., Topsakal, V., Russo, A., Taibah, A., & Sanna, M. (2012). Rate of recurrent vestibular schwannoma after total removal via different surgical approaches. Ann Otol Rhinol Laryngol, 121(3), 156-161. doi:10.1177/000348941212100303
20. Colletti, V., & Fiorino, F. (2003). Middle fossa versus retrosigmoid-transmeatal approach in vestibular schwannoma surgery: a prospective study. Otol Neurotol, 24(6), 927-934. doi:10.1097/00129492-200311000-00018
21. Colletti, V., & Fiorino, F. (2005). Is the middle fossa approach the treatment of choice for intracanalicular vestibular schwannoma? Otolaryngol Head Neck Surg, 132(3), 459-466. doi:10.1016/j.otohns.2004.09.027
22. Mangham, C. A., Jr. (2004). Retrosigmoid versus middle fossa surgery for small vestibular schwannomas. Laryngoscope, 114(8), 1455-1461. doi:10.1097/00005537-200408000-00026
23. Chovanec, M., Zvěřina, E., Profant, O., Skřivan, J., Cakrt, O., Lisý, J., & Betka, J. (2013). Impact of video-endoscopy on the results of retrosigmoid-transmeatal microsurgery of vestibular schwannoma: prospective study. Eur Arch Otorhinolaryngol, 270(4), 1277-1284. doi:10.1007/s00405-012-2112-6
24. Bi, Y., Ni, Y., Gao, D., Zhu, Q., Zhou, Q., Tang, J., . . . Lou, M. (2021). Endoscope-Assisted Retrosigmoid Approach for Vestibular Schwannomas With Intracanalicular Extensions: Facial Nerve Outcomes. Front Oncol, 11, 774462. doi:10.3389/fonc.2021.774462
25. Cândido, D. N. C., Rassi, M. S., Ceccato, G. H. W., de Oliveira, J. G., & Borba, L. A. B. (2020). Microsurgical Resection of Trigeminal Schwannomas: 3-Dimensional Operative Video. Oper Neurosurg, 18(1), E18. doi:10.1093/ons/opz097
26. Lucidi, D., Marchioni, D., Bisi, N., Calvaruso, F., Presutti, L., Alicandri-Ciufelli, M., & Donvito, S. (2025). Prognostic Factors for Facial Nerve Outcome after Vestibular Schwannoma Surgery: A 12-Year Multicentric Retrospective Study. Otol Neurotol, 46(8), 978-983. doi:10.1097/mao.0000000000004582
27. Aihara, N., Yamada, H., Takahashi, M., Inagaki, A., Murakami, S., & Mase, M. (2017). Postoperative Headache after Undergoing Acoustic Neuroma Surgery via the Retrosigmoid Approach. Neurol Med Chir (Tokyo), 57(12), 634-640. doi:10.2176/nmc.oa.2017-0108
28. Hillman, T., Chen, D. A., Arriaga, M. A., & Quigley, M. (2010). Facial nerve function and hearing preservation acoustic tumor surgery: does the approach matter? Otolaryngol Head Neck Surg, 142(1), 115-119. doi:10.1016/j.otohns.2009.10.015
29. Arts, H. A., Telian, S. A., El-Kashlan, H., & Thompson, B. G. (2006). Hearing preservation and facial nerve outcomes in vestibular schwannoma surgery: results using the middle cranial fossa approach. Otol Neurotol, 27(2), 234-241. doi:10.1097/01.mao.0000185153.54457.16
30. Kunigelis, K., Yang, A., & Youssef, A. S. (2018). Endoscopic Assisted Retrosigmoid Approach for Cerebellopontine Angle Epidermoid Tumor. J Neurol Surg B Skull Base, 79(Suppl 5), S413-s414. doi:10.1055/s-0038-1669978
31. Nickele, C. M., Akture, E., Gubbels, S. P., & Başkaya, M. K. (2012). A stepwise illustration of the translabyrinthine approach to a large cystic vestibular schwannoma. Neurosurg Focus, 33(3), E11. doi:10.3171/2012.7.Focus12208
32. Gibbon, F. L., Lindner, R. J., Vial, A. D. M., da Silva, G. G., Palavani, L. B., Semione, G., . . . Lavinsky, J. (2025). Translabyrinthine versus Retrosigmoid Approach for Vestibular Schwannoma: A Systematic Review and An Updated Meta-Analysis. Otolaryngol Head Neck Surg, 172(3), 774-786. doi:10.1002/ohn.1031
33. Hedjrat, A., Schwager, K., Hofmann, E., & Behr, R. (2018). Postoperative Cochlear Obliteration after Retrosigmoid Approach in Patients with Vestibular Schwannoma. J Neurol Surg B Skull Base, 79(4), 343-348. doi:10.1055/s-0037-1608649
34. Fujita, Y., Uozumi, Y., Akutsu, N., Sasayama, T., & Kohmura, E. (2024). Delayed facial palsy after resection of vestibular schwannoma: does it influence long-term facial nerve functional outcomes? J Neurosurg, 140(6), 1605-1613. doi:10.3171/2023.10.Jns231581
35. Gharabaghi, A., Samii, A., Koerbel, A., Rosahl, S. K., Tatagiba, M., & Samii, M. (2007). Preservation of function in vestibular schwannoma surgery. Neurosurgery, 60(2 Suppl 1), ONS124-127; discussion ONS127-128. doi:10.1227/01.Neu.0000249245.10182.0d
36. Yang, Q., Li, C., Ye, M., Zhou, X., Li, W., & Li, F. (2024). Effect of central sensitization on postoperative cognitive dysfunction in total knee arthroplasty patients: a retrospective study. Front Neurol, 15, 1509197. doi:10.3389/fneur.2024.1509197
37. De Marco, R., Froelich, S., Albera, A., Garbossa, D., & Zenga, F. (2025). A systematic review on the role of the endoscope in the surgical management of cerebellopontine angle tumors: is it time to draw the conclusion? Eur Arch Otorhinolaryngol. doi:10.1007/s00405-025-09427-4
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