Impact of fundal extension on hearing after surgery for vestibular schwannomas

Otol Neurotol. 2012 Apr;33(3):455-8. doi: 10.1097/MAO.0b013e318245cf01.


Objective: To compare hearing preservation after surgery for intracanalicular vestibular schwannomas with or without fundal extension.

Study design: Retrospective chart review.

Patients: Patients with intracanalicular tumors (≤ 10-m maximal dimension) undergoing retrosigmoid craniotomy between 2001 and 2010.

Intervention: Preoperative and postoperative audiograms, preoperative magnetic resonance imaging, and operative reports were reviewed.

Main outcome measures: Preoperative and postoperative hearing (American Academy of Otolaryngology-Head and Neck Surgery classification).

Results: Complete data for 53 patients (27 female and 24 male subjects, sex was not recorded for 2 patients) meeting selection criteria was available. Fundal involvement was identified in 39 (73.6%) of the 53 patients. The remaining 14 patients did not have tumor with fundal extension (26.4%). Average tumor size for patients with fundal extension (+FE) was 6.9 ± 2.2 mm and without fundal extension (-FE) was 8.2 ± 1.9 mm (p = 0.05, Student's t test). Average preoperative speech discrimination score for the entire study was 90.5 ± 11.8 (n = 53). After retrosigmoid approach for tumor resection, 79% of patients (42/53) had preserved hearing defined as American Academy of Otolaryngology-Head and Neck Surgery class A, B, or C. Average postoperative speech discrimination score for these patients was 89.3 ± 12.1, and average postoperative pure-tone average was 35.9 ± 9.1%. Eighty-five percent (33/39) of +FE patients had preserved hearing (class A, B, or C). In contrast, 64% (9/14) of -FE patients had hearing preserved (class A, B, or C; Fisher's exact test, p = 0.034).

Conclusion: Hearing preservation rate after retrosigmoid craniotomy for intracanalicular vestibular schwannomas may be superior for tumors with fundal extension compared with tumors that do not extend to the fundus.

MeSH terms

  • Adult
  • Aged
  • Audiometry, Pure-Tone
  • Autoradiography
  • Craniotomy
  • Female
  • Hearing / physiology*
  • Humans
  • Magnetic Resonance Imaging
  • Male
  • Middle Aged
  • Neuroma, Acoustic / pathology*
  • Neuroma, Acoustic / surgery*
  • Otologic Surgical Procedures
  • Postoperative Care
  • Postoperative Complications / epidemiology
  • Postoperative Period
  • Retrospective Studies
  • Speech Discrimination Tests
  • Treatment Outcome