Management of Intralabyrinthine Schwannomas Including Surgical Tumor Removal and Hearing Rehabilitation with Cochlear Implants

By June 7, 2019

Plontke, Stefan K.1; Caye-Thomasen, Per2; Strauss, Christian3; Wickenhauser, Claudia4; Wagner, Luise1; Fröhlich, Laura1; Kösling, Sabrina5; Rahne, Torsten1
1 Department of Otorhinolaryngology, Head & Neck Surgery, Martin Luther University Halle-Wittenberg, University Medicine Halle, Germany;
2 Department of Oto-rhino-laryngology, Head and Neck Surgery, and Audiology, University Hospital Rigshospitalet, Copenhagen, Denmark;
3 Department of Neurosurgery, Martin Luther University Halle-Wittenberg, University Medicine Halle, Germany;
4 Institute of Pathology, Martin Luther University Halle-Wittenberg, University Medicine Halle, Germany;
5 Department of Radiology, Martin Luther University Halle-Wittenberg, University Medicine Halle, Germany.

Intralabyrinthine schwannomas (ILS) are a rare differential diagnosis of sudden hearing loss and vertigo. The common management of these tumors is often a “wait-and-test-and-scan (W&T&S)” strategy. We describe the managment of these tumors including surgical removal through subtotal or partial cochleoectomy and/or labyrinthectomy and cochlear implantation (CI).

Study Design: retrospective
Setting: tertiary referral center
Patients: 35 patients (20 with intracochlear, 3 intravestibular, 3 intravestibulo-cochlear, 5 transmodiolar (including 2 with cerebello-pontine angle (CPA) extension, 1 translabyrinthine, 1 transotic with CPA and 2 multilocular tumor location)
Intervention(s): Thirty patients received surgery for tumor removal, with 26 patients receiving a cochlear implant in the same session.

Main Outcome Measure(s): hearing outcome (monosyllables at 65 dB HL in quiet), adverse events
Results: In all but one case, hearing rehabilitation with CI was successful, with good word recognition for monosyllables in quiet: average 35% at 65 dB SPL at first fitting and 70% at 12 months follow up. In cases of total removal of transmodiolar tumors reaching the CPA (x2), the cochlea could not be preserved.

Surgical removal of ILS is recommended before tumor growth leads to a complete filling of the cochlea or before a transmodiolar or transmacular growth complicates surgical removal and cochlear implantation. Radiotherapy of ILS may lead to destruction of the spiral ganglion cells hindering hearing rehabilitation with CI. If done early enough, cochlear implantation after surgical removal of ILS appears as an interesting option for auditory rehabilitation and an alternative to a “W&T&S” strategy.