Patients with vestibular schwannoma undergoing surgical removal of the tumor one day before the surgery: objective methods videoHead Impulse test, cervical vestibular evoked myogenic potentials, air calorics, clinical otoneurologic examination, functional magnetic resonance subjective methods: questionnaires (DHI,..) one week after the surgery: objective methods videoHead Impulse test, clinical otoneurologic examination, functional magnetic resonance subjective methods: questionnaires (DHI,..)

The healty patients without the history of vestibular disorder. objective methods videoHead Impulse test, cervical vestibular evoked myogenic potentials, functional magnetic resonance subjective methods: questionnaires (DHI,..)

Vestibular schwannoma resection leads to partial or combined acute unilateral peripheral or combined vestibular lesion.The organism responds with the process of central vestibular compensation.

Fuctional magnetic resonance (fMRI) could display certain areas of the brain and its pathways involved in the process of central compensation resulting from the acute unilateral vestibular lesion.

We aim to compare pre- and post- operative fMRI results with the results of healthy controls to see whether there is a difference in activating vestibular centers and maintaining the equilibrium after the central compensation occurs. Different level of activation of vestibular cortical areas, resp. differences in activation in response to optokinetic stimulation will be measured in healthy controls and study group. Evaluation of functional brain MRI will be provided by expert neuroradiologist. Vestibular function will be assessed by objective vestibular tests (videonystagmography, video Head Impuls Test) and by subjective scales (questionnaires - The Penn Acoustic Neuroma Quality-of-Life scale, Dizziness Handicap Inventory - in both the higher score indicates higher handicap).

Evaluation of differences between control and study group in functional brain MRI in response to wide field optokinetic stimulation. Differences in size and level of activation of vestibular cortical areas will be evaluated by expert neuroradiologist.