This work was supported by NIH grants U24 DC008559 and U24DC008625. The authors have no other funding, financial relationships, or conflicts of interest to disclose.
Temporal bone histopathology in neurofibromatosis type 2†
Article first published online: 10 JUN 2011
Copyright © 2011 The American Laryngological, Rhinological, and Otological Society, Inc.
Volume 121, Issue 7, pages 1548–1554, July 2011
How to Cite
Nam, S.-I., Linthicum, F. H. and Merchant, S. N. (2011), Temporal bone histopathology in neurofibromatosis type 2. The Laryngoscope, 121: 1548–1554. doi: 10.1002/lary.21822
- Issue published online: 16 JUN 2011
- Article first published online: 10 JUN 2011
- Accepted manuscript online: 27 APR 2011 10:25AM EST
- Manuscript Accepted: 15 MAR 2011
- Manuscript Revised: 4 MAR 2011
- Manuscript Received: 4 FEB 2011
- Neurofibromatosis type 2;
- bilateral acoustic neuroma;
- temporal bone histopathology;
To describe the histopathologic findings in the temporal bone in patients with neurofibromatosis type 2 (NF2). The literature contains limited data on otopathology of NF2.
Basic science study.
Twenty-six temporal bones from 16 patients with NF2 were examined by light microscopy. The diagnosis of NF2 was made on the basis of bilateral cochleovestibular schwannomas. Clinical information was obtained from review of the medical records.
The tumors were multicentric in origin in 19 of 26 (73%) ears. Typically, tumors were seen arising within the internal auditory canal and from various locations within the labyrinth. The majority of schwannomas showed high cellularity with involvement of the labyrinth. Most cases showed significant degrees of degeneration of sensory and neural elements within the cochlea. Fusion tumors were sometimes seen as a result of a schwannoma merging with an adjacent meningioma. Fifteen of 26 (58%) ears showed facial nerve involvement by schwannoma.
Cochleovestibular schwannomas in NF2 are aggressive neoplasms; they are often multicentric and demonstrate a propensity to involve the labyrinth. There is often associated secondary degeneration within the cochlea. These features make total removal of these tumors and their removal with preservation of hearing more difficult than with sporadic unilateral cochleovestibular schwannoma.