Preservation of hearing following awake surgery via the retrosigmoid approach for vestibular schwannomas in eight consecutive patients



Hearing preservation in patients with vestibular schwannomas remains difficult by microsurgery or radiosurgery.


In this study, awake surgery via the retrosigmoid approach was performed for vestibular schwannomas (volume, 11.6 ± 11.2 ml; range, 1.3–26.4 ml) in eight consecutive patients with preoperative quartering of pure tone audiometry (PTA) of 53 ± 27 dB.


After surgery, hearing was preserved in seven patients and improved in one patient. The postoperative quartering PTA was 51 ± 21 dB. Serviceable hearing (class A + B + C) using the American Association of Otolaryngology-Head and Neck Surgery (AAO-HNS) classification was preserved in all patients. Preoperative useful hearing (AAO-HNS class A + B) was observed in three patients, and useful hearing was preserved in all three of these patients after surgery. In addition, useful facial nerve function (House-Blackmann Grade 1) was preserved in all patients.


These results suggest that awake surgery for vestibular schwannomas is associated with low patient morbidity, including with respect to hearing and facial nerve function.

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Correspondence to Nobusada Shinoura.

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All procedures performed in studies involving human participants were in accordance with the ethical standards of the institutional and/or national research committee and with the 1964 Helsinki declaration and its later amendments or comparable ethical standards.

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Shinoura, N., Midorikawa, A., Hiromitsu, K. et al. Preservation of hearing following awake surgery via the retrosigmoid approach for vestibular schwannomas in eight consecutive patients. Acta Neurochir 159, 1579–1585 (2017).

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  • Awake surgery
  • Vestibular schwannomas
  • Facial nerve
  • Hearing