Related Experiment Video
Updated: Sep 23, 2026

A Unified Methodological Framework for Vestibular Schwannoma Research
Published on: June 20, 2017
Tumor Nerve of Origin and Hearing Preservation Outcomes for Patients With Small Vestibular Schwannomas Undergoing
Pawina Jiramongkolchai1, Magnus Wahlin2, Alexandra Vacaru2
1Department of Otolaryngology-Head and Neck Surgery, Washington University in St. Louis, St. Louis, Missouri.
Objective:
To evaluate hearing preservation (HP) outcomes based on tumor nerve origin for patients with small sporadic vestibular schwannomas (VS) undergoing microsurgical resection using the middle cranial fossa (MCF) approach.
Study Design:
Retrospective single-institution study.
Setting:
Tertiary academic institution.
Patients:
Adults 18 years or older with small sporadic VS (≤15 mm).
Intervention:
MCF.
Main Outcome Measure:
Hearing preservation is defined as a word recognition score of ≥50%.
Results:
Of the 189 consecutive patients who underwent surgery, 164 (89%) had intraoperative identification of the tumor nerve of origin. Of those 164 patients, 88 (54%) had inferior vestibular nerve (IVN) tumors, and 76 (46%) had superior vestibular nerve (SVN) tumors. Hearing was preserved in 83% of patients with SVN tumors compared with 49% of patients with IVN tumors. When stratified by size, the rate of HP was highest (91%) for tumors of SVN origin ≤5 mm in size. In multivariate analysis, patients with SVN tumors ≤5 mm in size had a 7.5-fold increase (95% CI: 1.60-34.9) in HP compared with patients with SVN tumors larger than 10 mm in size. There was no significant difference in facial nerve outcomes between the 2 groups. At initial follow-up, 70 (92%) patients with SVN tumors and 83 (94%) patients with IVN tumors had a HB 1/2, respectively.
Conclusions:
Patients with small SVN tumors have a significantly higher likelihood of HP as well as shorter operative time compared with IVN tumors, suggesting that, in appropriate candidates, early surgical intervention may be beneficial.
