The CyberKnife^® is a form of radiosurgery, which means that instead of a scalpel, a the surgeon uses a single, high dose of radiation, which eliminates the diseased area safely and effectively. Only the tissue being treated receives a very high dose of radiation while the surrounding tissue remains unharmed. Radiosurgery is painless and bloodless and involves no risk of surgical complications such as infection, hemorrhage or leakage of cerebral spinal fluid.

Although the entire procedure takes several hours, the actual treatment itself takes just 15 minutes to one to three hours, depending on the size of the lesion(s) being treated. If there are multiple tumors are present or if the tumor spreads to another area, radiosurgery can be repeated. There is no risk of surgical complications such as infection, hemorrhage or leakage of cerebral spinal fluid.

Other radiosurgery delivery systems exist; however, not all radiosurgery is the same.  The following chart compares The CyberKnife^® with the Gamma Knife and other Linac systems:

		CyberKnife®	Gamma Knife®	Other Linac Systems (Elekta Synergy®, Novalis®, Varian Trilogy®, TomoTherapy®)
	Is it dedicated just to radiosurgery?	YES	YES	NO
	What area of the body is treatable with radiosurgical precision?	whole body	Brain/Skull base (minus extreme lateral)	Varies
	IMRT dosimetry Method	YES	NO	YES
	IGRT Set-up Visualization	YES	NO	YES
	Can do “conventional” radiotherapy and/or IMRT With IMRT (Intensity Modulated Radiation Therapy), the intensity of the radiation can be changed during treatment to spare more adjoining normal tissue than is spared during conventional radiation therapy. An increased dose of radiation can be delivered to the tumor using IMRT. Intensity modulated radiation therapy is a type of “conformal radiation”, which shapes or conforms radiation beams to the shape of the tumor, causing more damage to the tumor and less damage to surrounding healthy tissues than conventional external beam radiation treatments.	NO	NO	YES
	Rigid Brain or Body Frame required for radiosurgical accuracy	NO	YES	YES
	Capable of conformally and homogeneously treating an irregularly shaped tumor under 3.5cm	YES	NO	YES
	Capable of fractionated radiosurgery to better preserve critical adjacent tissue	YES	NO	YES
	Tracks patient-induced motion with radiosurgical precision (<1mm)	YES	NO	Varies by method and manufacturer
	Tracks spine motion with radiosurgical precision (<1mm)	YES	N/A	NO
	Tracks organ induced target volume motion with radiosurgical precision (<1mm)	YES	N/A	NO
	Tracks respiration induced organ motion with radiosurgical precision (<1.5mm)	YES	N/A	NO
	Capable of real-time sub-millimeter translational and rotational beam adaptation to target volume motion	YES	N/A	NO