CyberKnife vs. Gamma Knife

Often times, we are asked about how the CyberKnife is different from the Gamma Knife. Both the CyberKnife and Gamma Knife are the most widely used stereotactic radiosurgery (SRS) devices and despite the name, SRS is actually a "knifeless" surgery. While the Gamma Knife treats with multiple beams simultaneously, the CyberKnife uses a single high-energy photon beam fixed to a robot arm. The arm directs the beam to different positions during the course of treatment, all converging in the treatment target.

CyberKnife is Non-Invasive
Unlike the Gamma Knife, a head frame is NOT required for sub-millimeter accuracy. Instead, the patient's head is stabilized and immobilized with a firm plastic mask, and the robot is guided by a series of X-ray images of the skull taken during treatment. The position of the skull is updated in real-time, and the robot adjusts the beam to account for any skull movement. Thus, the CyberKnife SRS for cranial lesions is non-invasive.

CyberKnife Can Divide the Treatment into Several Fractions
Because the CyberKnife does not require rigid immobilization in a frame, it is capable of breaking up the full radiosurgical treatment dose into several fractions and delivering it on several consecutive days. Doing so can help to preserve sensitive normal tissues from radiation injury. It is particularly an advantage when the treatment targets in the brain are in close proximity to sensitive structures such as the optic nerves and the brainstem. In addition, breaking up the treatment into several fractions often allows us to treat larger and more complex lesions on the Cyberknife, which otherwise could not be treated with the Gamma Knife.

CyberKnife Can Treat Extracranial Lesions
Another difference between the CyberKnife and the Gamma Knife is that the CyberKnife, unlike the Gamma Knife is capable of treating lesions outside of the head. Extracranial radiosurgery has enormous potential as a standard treatment option. Data have demonstrated promising results for certain tumors of the liver, lung, and spine, and for radiation-resistant histologies. CyberKnife technology is especially useful in treating tumors that move with respiration, such as lung and liver lesions, with sub-millimeter precision.