What is Robotic Stereotactic Radiosurgery, e.g. Cyberknife?
Stereotactic radiosurgery is a precise, painless, non-invasive radiation treatment that utilizes very accurately targeted, large “killing” doses of radiation. This non-invasive “operation” has proven to be an effective alternative to surgery or conventional radiation for treating many small tumors and a few other select medical disorders. CyberKnife Centers of Tampa Bay provide a number of online videos and case studies to help you understand more about the CyberKnife technology.
Multiple beams of high energy radiation are delivered from multiple points outside of the body and converge precisely at the tumor or lesion inside the body. Each individual beam is not sufficient to cause harm, but the convergence of all the beams at the tumor results in the lesion receiving a very high dose of radiation while sparing nearby normal tissue.
CyberKnife radiosurgery is so precise, radiation beams can be sculpted to small, complex-shaped tumors near critical structures, such as hearing and vision nerves. This ability to accurately irradiate only the tumor and protect healthy tissue allows the CyberKnife to treat many lesions which may be considered inoperable or untreatable with other radiosurgery systems… giving many patients new hope.
Standard stereotactic techniques rely on a rigid metal frame fixed to a patient’s skull for head immobilization and target localization. However, such frame-based systems have numerous limitations, including:
- Restricting treatment to the brain,
- Limiting the possible angles which radiation could be delivered,
- Causing considerable discomfort for the patient.
In contrast to the standard frame-based radiosurgical instruments, the CyberKnife uses noninvasive image-guided localization, and a robotic delivery system. This combination of technologies enables the CyberKnife to overcome the limitations of older frame-based radiosurgery such as the Gamma Knife and LINAC
The CyberKnife belongs to a new class of radiotherapy techniques called IGRT (image-guided radiotherapy. 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 which 'matches' the shape of the prostate and spares adjacent normal anatomy (bladder and rectum).
For more information and updates of new radiation techniques, click here.