Radiosurgery of epilepsy

Since 1982 a series of 11 epileptic patients have been treated with stereotactic radiosurgery. Patients were intracranially recorded with cortical and deep electrodes until the location of the epileptogenic focus was determined. A deep electrode was stereotactically placed at this point to confirm the accuracy of the location. All patients received radiosurgery with a gamma source and a dose of 10 to 20 Gy, except two of them in which a betatron was used. The results were: Total disappearance of the crises and withdrawal of medication: 4 cases (36%). More than 80% reduction of crises: 3 cases (27%). More than 50% reduction of crises: 2 cases (18%). Less than 50% reduction of crises: 2 cases (18%). No complications were observed, even in those cases in which the focus was located near critical areas of the brain. The efficacy of the low doses used accounts for non-destructive mechanisms, probably mediated by a neuronal plasticity phenomenon, as experimental studies suggest. The lack of complications can make this therapeutic approach an alternative to be considered when critical areas are involved.