Intended Near-Total Removal of Koos Grade IV Vestibular Schwannomas: Long Term Results in a Single Center Cohort
Birgit Westermann, Daniel Zumofen, Michel Röthlisberger, Luigi Mariani, Heike Neddersen
Introduction: Radical microsurgical removal of large (Koos IV) vestibular schwannomas is associated with a high risk of permanent neurological deficit, mainly facial palsy. Alternatives to this approach are needed.
Objective: A treatment paradigm characterized by intended near-total removal of large vestibular schwannomas followed by “wait-and-scan” was associated with good clinical results and low recurrence rates in the short-term. The success of this strategy needs a confirmation in the long-term.
Methods:  Zumofen DW, Guffi T, Epple C, Westermann B, Krähenbühl AK, Zabka S, Taub E, Bodmer D, Mariani L. Intented Near-Total Removal of Koos Grade IV Vestibular Schwannomas: Reconsidering the Treatment Paradigm. Neurosurgery; 82:202-210, 2018.
The fourty four patients included in the published series had consented to their prospective long term outcome monitoring and assessment. We will assess outcome as of June 30. 2019.
Results: We will report on the recurrence rate, on the volumetric fate, on the type and rate of additional treatments, as well as on the clinical condition of these patients as per end of June 2019; the shortest and the longest follow-up will be 3.5 and 9.5 years, respectively.
Conclusions will depend on the results of the analysis that will be performed after June 30., 2019.