Stereotaxic Irradiation in Treatment of Cases with Vestibular Schwannomas

S.V. Zolotova, N.G. Nikonova, S.R. Ilyalov, A.V. Golanov, D.N. Kapitanov, T.M. Kotelnikova, O.I. Soboleva, V.V. Kostyuchenko, G.E. Gorlachev, N.V. Artyunov, A.E. Podoprigora, S.V. Serkov

Burdenko Research Institute of Neurosurgery, Moscow, Russia

 

Development of neurovisualization methods has resulted in considerable increase of a rate of vestibular schwannoma (VS) diagnosis at an early stage, i.e. before appearance of hypertensive-hydrocephalic and stem symptoms. Such cases can be treated with stereotaxis radiosurgery (SRS) and radiotherapy (SRT). There were 220 cases with VS, aged 14-81, who were treated at our Institute in 2005-2008. Diagnosis was verified histologically in 62 cases (28%) after tumor removal; it was done on the basis of clinical and rentgenologic data in the rest patients. SRS with applying the Gamma-Knife apparatus and the Novalis linear accelerator was used in 160 and 38 casesrespectively; SRT was carried out in 22 cases. Data of control examination were available in 179 patients. A tumor growth was arrested in 99% of cases. Hydrocephalus, which developed in 8 cases, demanded use of a shunting system in 3 of them. Dynamics of hearing disorders was estimated on the basis of the following criteria: 1 - hearing stabilization or a number of cases, whose hearing remained unchanged (except the deaf): 2 - preserved “useful” hearing or changes of hearing in cases with its good level before treatment (the score of I-II according to Gardner-Robertson scale). These indices were 69% and 61.7%, respectively. There were transient functional disorders of the trigeminal (paresthesia or hemifacial spasm) and facial (the score of I-II according to House-Breckman scale) nerves, watched in 9% and 6% of cases, respectively.

Today SRS and SRT become methods of choice for cases with VS. A long-term catamnestic follow-up (up to 4 years) has demonstrated, that they are characterized by excellent control of tumor growth and preserved of function of craniocerebral nerves.