Evidence map›Paper›PMID 42199887›Full record

ArticleFrontiers in surgery2026

Combined presigmoid retrolabyrinthine and retrosigmoid approach for large vestibular schwannoma: a case report.

Mitsuru Kojima, Ryota Tamura, Konosuke Ishikawa, Taichi Sayanagi, Kosuke Karatsu, Ryo Ueda, Masahiro Toda

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In one paragraph

Article in Frontiers in surgery, 2026. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Not yet cited in PubMed.

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4 · The record

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5 · Who and what money

Authors and funding

7 authors.

Mitsuru KojimaDepartment of Neurosurgery, Keio University School of Medicine, Tokyo, Japan.
Ryota TamuraDepartment of Neurosurgery, Keio University School of Medicine, Tokyo, Japan.
Konosuke IshikawaDepartment of Neurosurgery, Keio University School of Medicine, Tokyo, Japan.
Taichi SayanagiDepartment of Neurosurgery, Keio University School of Medicine, Tokyo, Japan.
Kosuke KaratsuDepartment of Neurosurgery, Keio University School of Medicine, Tokyo, Japan.
Ryo UedaDepartment of Neurosurgery, Keio University School of Medicine, Tokyo, Japan.
Masahiro TodaDepartment of Neurosurgery, Keio University School of Medicine, Tokyo, Japan.

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

Background: The retrosigmoid approach is widely used for vestibular schwannoma resection. If the tumor is large, significant cerebellar retraction may be required, which can cause cerebellar edema. The presigmoid retrolabyrinthine route preserves the labyrinth and reduces cerebellar retraction and manipulation but provides only a narrow surgical corridor. We report the use of a combined approach to safely resect a large vestibular schwannoma with brainstem compression while avoiding complete postoperative deafness. Methods: A 24-year-old man presented with a large right vestibular schwannoma causing considerable brainstem compression. A combined temporal-suboccipital craniotomy with near-total mastoidectomy was performed to expose the sigmoid sinus while preserving the labyrinth. Microsurgical dissection was performed via the retrosigmoid corridor, while a rigid endoscope inserted through the presigmoid route provided direct visualization of the brainstem side. Results: This dual-corridor, dual-visualization technique enabled safe subperineural tumor removal and identification of the facial nerve. Gross total resection was achieved, and the postoperative course was uneventful. At approximately 6 months postoperatively, facial nerve function remained normal (House-Brackmann grade I). Formal postoperative pure-tone audiometry demonstrated residual hearing on the operated side, predominantly in the low-frequency range. Although serviceable hearing was not preserved, complete postoperative deafness was avoided. Conclusion: In large vestibular schwannomas with vertical brainstem extension, retrosigmoid resection alone may require excessive cerebellar retraction. Adding a presigmoid retrolabyrinthine corridor improves brainstem access, minimizes cerebellar retraction and manipulation, and facilitates safe tumor removal. This combined approach is a practical strategy for patients with significant brainstem compression.

Indexed as

combined approachpresigmoid approachretrolabyrinthine approachretrosigmoid approachvestibular schwannoma

Identifiers

PMID42199887
PMCPMC13199334

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Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.