Dose plan of gamma knife radiosurgery by three-dimensional CISS images localized on MRI and CT under stereotactic conditions for glossopharyngeal neuralgia. CISS = Interference in steady state; MRI = Magnetic resonance imaging; CT = Computed tomography. The right cisternal portion of the glossopharyngeal nerve, close to the glossopharyngeal meatus of the jugular foramen, was irradiated by a maximum dose of 80 Gy, using a single 4 mm collimator (yellow circle showing 95% isodose line and green circle showing 16 Gy isodose)