Gamma Knife® radiosurgery A minimally invasive stereotactic radiosurgery procedure that utilises a technology that focuses beams of radiation onto a very small spot (isocenter) within the trigeminal nerve root. The procedure is performed with a stereotactic reference frame that is temporarily attached to the head of the person undergoing the procedure, therefore, local anaesthesia is required. The dominant number of studies and volume of clinical outcomes data for stereotactic radiosurgery for trigeminal neuralgia utilises this technique.