The CyberKnife is a linear accelerator treatment machine for radiosurgery and
radiotherapy. Linear accelerator machines utilizr X-rays that are targeted at the tumor to destroy the growth
of the cells. All high level radiosurgery linear accelerators (Novalis Tx, Axesse and CyberKnife) and cobalt machines (Gamma Knife) are both robotic and image guided.
The CyberKnife offers another approach to radiosurgery. Radiation is delivered by means of a small
linear accelerator mounted on a industrial like robotic arm. The technology provides the physician with
the ability to target tumors and lesions throughout the body that may be too large for other more precise
technology. The CyberKnife can be used to treat tumors in the brain and body, but is primarily used for the body at this time. It may be used as a one session treatment (radiosurgery) but more often is used as a fractionated
treatment over time. Treatments over time, allow the health tissue that resides close to a tumor which received overlapping radiation
to recover before the next session.
Image guidance technology tracks the patient and the tumor during treatment, adjusting the radiation beams after a short
lapse if there is movement from the patient. This also means that some extra radiation will be received by the
patient from the X-ray image guided tracking device which is constantly scanning during the treatment.
Since most treatments are delivered over several days or a week, fiduicials may be implanted
in the outer cartiledge of the head or an appropriate position around a body tumor
to secure a removal frame for the continuing treatment. These will be removed
after all treatments are completed and do not result in any substantial inconvience or pain for the patient.