gms | German Medical Science

58. Jahrestagung der Deutschen Gesellschaft für Neurochirurgie e. V. (DGNC)

Deutsche Gesellschaft für Neurochirurgie (DGNC) e. V.

26. bis 29.04.2007, Leipzig

Predictive factors for early facial nerve function after vestibular schwannoma surgery

Faktoren zur Voraussage der frühen Funktion des N. Facialis nach operativer Entfernung von Vestibularis Schwannome

Meeting Abstract

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  • corresponding author V. Gerganov - International Neuroscience Institute (INI), Neurochirurgie, Hannover
  • A. Samii - International Neuroscience Institute (INI), Neurochirurgie, Hannover
  • M. Samii - International Neuroscience Institute (INI), Neurochirurgie, Hannover

Deutsche Gesellschaft für Neurochirurgie. 58. Jahrestagung der Deutschen Gesellschaft für Neurochirurgie e.V. (DGNC). Leipzig, 26.-29.04.2007. Düsseldorf: German Medical Science GMS Publishing House; 2007. DocDO.04.05

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

Published: April 11, 2007

© 2007 Gerganov 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: To determine the significance of preoperatively available clinical and radiological parameters for predicting early facial nerve function (FNF) after vestibular schwannoma (VS) surgery.

Methods: A retrospective study of 99 patients of VS operated consecutively by a single neurosurgeon, using the same technique, has been performed. The following data were collected for each patient: age at first symptom, age at surgery, interval between onset of clinical signs and symptoms to surgery, sex, clinical and neurological data including cranial nerve function and audiogram. FNF before surgery and 10-14d. following surgery was assessed according to the House-Brackmann Classification. The radiological parameters analysed included tumor size (Hannover Classification T1-T4b), volume, extension in relation to the internal auditory canal (IAC), width and length of the intrameatal tumor portion, tumor-fundus distance and dimensional changes of the IAC. Statistical analysis included parametric independent t-test and paired t-test, the nonparametric Kruskal-Wallis and Mann- Whitney U, Chi-square and Pearsons correlation tests.

Results: The following clinical parameters correlated significantly with postoperative FNF deterioration: headache as an initial symptom, ataxia at presentation and preoperative FNF deficit. The following clinical parameters did not correlate significantly: age, sex, preoperative hearing level, trigeminal and caudal nerves nerve malfunction and hydrocephalus. Tumor extension and volume, as well as its growth in all directions had a significant correlation with facial nerve outcome (p<0.05), but anterior and/or caudal extensions had a more significant correlation than posterior and/or inferior extension (p<0.001). Polycyclic VS had a worse outcome compared to oval and round VS (p<0.05). Neither intrameatal length, intrameatal width nor tumor-fundus distance significantly influenced the outcome. The different angles and diameters of the IAC showed no significant correlation with FNF.

Conclusions: Numerous preoperatively available parameters may predict the early outcome of FNF following VS surgery. Especially tumor size, shape and extension pattern within the CP-angle show a significant statistical correlation.