Vestibular schwannomas are benign lesions of the ponto-cerebellar angle that are potentially dangerous because of their growth in a cramped space and the compressive phenomena they can cause. Stereotactic Gammaknife radiosurgery is a treatment option that can be offered for evolutive schwannomas smaller than 2.5-3 cm in size. It allows tumor stabilisation in 85% of cases with less than 1% facial nerve damage risk. There are controversial results regarding hearing preservation : percentages vary between 25 and 80% in the literature, depending on the criteria used and the post-treatment delay. Few studies have investigated changes in vestibular function and the impact on balance of radiosurgery, and their results are variable. These controversial results lead us to comprehensively assess the vestibular function and balance of these patients using a balance-specific quality of life questionnaire, in addition to objective overall vestibular assessments of vestibular function.