gms | German Medical Science

57th Annual Meeting of the German Society of Neurosurgery
Joint Meeting with the Japanese Neurosurgical Society

German Society of Neurosurgery (DGNC)

11 - 14 May, Essen

Residual tumour in vestibular schwannoma surgery – functional outcome and radiological behaviour – a 10-years-study

Resttumoren bei Vestibularschwannomen – funktionelle Ergebnisse und radiologisches Verhalten – eine 10-Jahres-Studie

Meeting Abstract

  • corresponding author M. Meinhardt - Neurochirurgische Universitätsklinik Würzburg
  • P. Kahle - Neurochirurgische Universitätsklinik Würzburg
  • T. Schweitzer - Neurochirurgische Universitätsklinik Würzburg
  • J. Helms - Universitätsklinik für Hals-, Nasen-, Ohrenkrankheiten Würzburg
  • K. Roosen - Neurochirurgische Universitätsklinik Würzburg

Deutsche Gesellschaft für Neurochirurgie. Japanische Gesellschaft für Neurochirurgie. 57. Jahrestagung der Deutschen Gesellschaft für Neurochirurgie e.V. (DGNC), Joint Meeting mit der Japanischen Gesellschaft für Neurochirurgie. Essen, 11.-14.05.2006. Düsseldorf, Köln: German Medical Science; 2006. DocSO.07.06

The electronic version of this article is the complete one and can be found online at:

Published: May 8, 2006

© 2006 Meinhardt et al.
This is an Open Access article distributed under the terms of the Creative Commons Attribution License ( You are free: to Share – to copy, distribute and transmit the work, provided the original author and source are credited.



Objective: 615 vestibular schwannomas from grade T3a -T4b were operated between 1994-2003 in a joint intervention by ENT- and neurosurgeons. In 89 operations (14%) some residual tumour could not be removed for different reasons. Clinical and MRI follow-up investigated regrowth rate and functional outcome. Type of residual tumour and reasons for incomplete removal were analyzed.

Methods: All tumours were removed under multimodal cranial nerve monitoring using AEP, trigeminal and facial EMG. The caudal cranial nerves were monitored if the tumour extended to the IX, X, XI, or XIIth nerve. Clinical investigation and serial MRI-scans were used to follow up patients. Serial clinical and radiological follow ups were used to investigate radiological behaviour of residual tumour and its clinical consequences. Operational reports were reviewed for reasons of subtotal removal.

Results: Strong adherence to cranial nerves (acoustic, facial or caudal), interfascicular growth pattern, drop of EMG or spontaneous firing, reduction of AEP and strong adherence to the brain stem or its vascular supply forced the surgeons to terminate the procedure. Average tumour size in case of incomplete resection was 27.8 mm vs.19.4 mm in complete resection cases. 86% of residual tumours consisted of residual capsula, a thin tumour layer or interfascicular tumour nests. Tumour decompression or gross total removal were exceptions. After 12 months a good to excellent facial nerve function was achieved in complete resection cases in 88% vs. 73% in incomplete resection cases. 65% (58) of residual tumours were not progressive, 10% (9) had progressive growth without any clinical or operative consequence, 6% (5) had to be re-operated and 17 (19%) were lost to follow-up. Mean follow-up of all patiens was 22.4 months (1-128).

Conclusions: A low percentage of tumour progression and an even lower rate of re-operations seem to justify a nearly complete resection if the tumour growth pattern or electrophysiological warnings force the surgeons to terminate the procedure in order to preserve neural function and therefore quality of life.