What is CyberKnife?

The CyberKnife Robotic Stereotactic Radiosurgery System is a non-invasive alternative to open surgery for the treatment of tumours anywhere in the body. The machine is considered a major advancement in the radiological treatment of cancer.
Stereotactic radiosurgery is a medical procedure that enables very high doses of radiation to be targeted directly at the tumour with pinpoint accuracy. This non-invasive “operation” has proven to be an effective alternative to surgery or standard radiation techniques, treating previously ‘hard to reach’ tumours or surgically complex tumours. Due to the pinpoint accuracy of the CyberKnife System it is also able to successfully treat areas of the body which have previously received the maximum dose of radiation. This pinpoint accuracy means that radiosurgery is now no longer limited to treating intracranial and spinal tumours.
Radiosurgery is limited to lesions that are well defined and usually no larger than 3-4cm. More than one lesion can be treated during the CyberKnife treatment. The location of the lesion is important. For example, lesions close to radiosensitive structures, such as the optic nerve, are not ideal targets for radiosurgery but can often be treated with fractionated radiosurgery.

#howHow does CyberKnife compare with other treatments?

Standard stereotactic radiosurgery techniques rely on a rigid frame fixed to the patient’s skull for head immobilisation. These systems are generally uncomfortable for the patient and they often require breath holding techniques, which may be difficult for some patients, require larger treatment areas and prolonged treatment times. This type of frame-based system means there are limited angles that the radiation can be delivered. Typically, a centre can only treat one patient per day. The CyberKnife System offers manoeuvrability and versatility that other systems cannot offer, therefore making it possible to treat tumours anywhere in the body, including the brain, spine, liver, lung, pancreas and prostate.  

How does CyberKnife work?

1. An advanced lightweight linear accelerator (LINAC) - this device is used to produce high energy ‘killing’ beams of radiation
2. A robot – this can point the linear accelerator from a wide variety of angles
3. X-Ray Cameras – Several X-Ray cameras are able to obtain frequent pictures of the patient during the treatment session. This information is then used to target the radiation beam with sub-millimetre accuracy.

The use of the robot in the CyberKnife System is vital in delivering radiation beams accurately whilst monitoring patient movement during the treatment. Any change in the position of the patient is detected by the cameras and then the robot adjusts its position to allow re-targeting of the linear accelerator before delivering the radiation beam. Use of the robot ensures that there is no need to manually reposition the patient during treatment as a result of movement, thereby slowing down the treatment process.