The CyberKnife belongs to a new class of radiotherapy techniques called image-guided radiotherapy (IGRT). The CyberKnife is unique in that it uses a compact linear accelerator (linac) mounted on an image-guided robotic arm to deliver multiple beams of high energy x-rays to a target. The ability of the CyberKnife to shape the profile of radiation to conform to the patient’s individual anatomy allows for maximum sparing of surrounding normal tissues.
The CyberKnife accomplishes this by accurately cross-firing approximately 150 beams of radiation at the target from multiple directions. The CyberKnife technology represents an improvement upon the most advanced conventional radiation therapy techniques: Intensity Modulated Radiotherapy (IMRT). Similar to IMRT, the CyberKnife can produce a highly conformal dose distribution that “matches” the shape of the tumor and spares adjacent normal anatomy (such as bladder and rectum for prostate cancer).