Gamma Knife Radiosurgery forVestibular Schwannomas

The current gamma knife radiosurgery technique involves the use of magnetic resonance imaging for targeting, the application of a lowmarginal dose (usually between 12 and 13 Gy) and highly conformal treatment planning using multiple small isocenters. This techniqueachieves an average tumor control rate of 95% and open surgery is needed in fewer than 2 to 3% of patients treated by gamma knife.Facial nerve function preservation is achieved in up to 99% of cases and chance of preserving serviceable hearing is usually between a70 to 80%. The introduction of ventriculoperitoneal drainage after radiosurgery is required for 1 to 8% of patients. Gamma knife radiosurgerycan be treatment of choice for the patients, where the diameter of the tumor is less than 3 cm.