Frequently Asked Questions

What is stereotactic radiosurgery?

Stereotactic radiosurgery is a non-surgical treatment in which high doses of focused radiation beams are delivered from multiple locations outside the body to destroy a tumor or lesion within the body. This procedure does not remove the tumor or lesion. Instead, it destroys tumor cells or stops the growth of active tissue. Traditional methods relied on a metal frame that was bolted to the skull in order to target the treatment. Because of the need for the metal frame, radiosurgery was not possible for tumors located outside of the head.

What is CyberKnife® Stereotactic Radiosurgery?

CyberKnife® is an entirely new approach to stereotactic radiosurgery because it can deliver targeted radiation to anywhere in the body, while minimizing exposure to surrounding normal tissue. It offers all of the advantages of radiosurgery, but without the need for a metal head frame.

With sub-millimeter accuracy, CyberKnife® can be used to treat tumors, cancers, vascular abnormalities and functional disorders. Best of all, it achieves surgical-like outcomes without surgery or incisions.

How does the CyberKnife® system work?

Using x-ray image cameras and computer technology similar to that used for cruise missile guidance, the CyberKnife® locates the tumor in the body. The medical team then precisely defines the area to be targeted, and the structures to be protected, after which the treatment planning computer evaluates the unique shape and location of the tumor to determine exactly how each of 50 to several hundred or more beams of radiation will target the tumor.

A small linear accelerator (high energy X-ray source) located on the CyberKnife's robotic arm delivers concentrated beams of radiation to the tumor from multiple positions and angles that are selected by the computer to minimize the damage to surrounding tissues. The range of motion offered by the robotic arm gives it maximum flexibility to reach tumor sites not accessible by other means.

The CyberKnife® system continually checks and compensates for any patient movement throughout the entire treatment process to ensure accuracy, maximizing the precision of the radiation treatment. Because the CyberKnife has pinpoint accuracy, it can deliver higher doses of radiation to treat tumors, ablating them as effectively as a surgeon's scalpel, but without the incision.

How is CyberKnife® different from other stereotactic radiosurgery systems like Gamma Knife?

The CyberKnife® system uses the combination of a robotic arm, linear accelerator (high energy X-ray source), and image guidance technology. Because of the flexibility of the robotic arm, the system is able to reach areas of the body that are unreachable by other radiosurgery systems. CyberKnife® can be used anywhere in the body, while existing radiosurgery systems typically only offer treatments to the brain and skull base area.

The CyberKnife® is able to locate the position of the tumor within the body without the use of an invasive head frame. It monitors and compensates for patient movement during treatment by a unique and very accurate process.

Is the CyberKnife® safe?

The CyberKnife® does not present the same problems as traditional surgery. There is no anesthesia, no incision, no bleeding and no post-operative pain or unpleasant anesthesia after effects. Because of its precision, CyberKnife® spares healthy tissue surrounding the targeted area in a manner not achievable with traditional radiation therapy. Over 20,000 people have received CyberKnife® treatments around the world.

What can I expect during CyberKnife® treatment?

Treatment follows five steps that may be performed on the same day or on separate days:

  • Initial Consultation
  • Treatment Preparation
  • Treatment Planning
    • Making a Mask or Body Immobilizer
    • CT Scan
    • Tumor Mapping/Computer Programming
  • CyberKnife Treatment
  • Follow-up

Click here for information on each of the steps.

Treatment is generally completed in one to five 30 to 120 minute sessions. Patients feel no pain during the treatment and are able to go home immediately afterward. San Diego CyberKnife® staff are always present to ensure your comfort and to make sure that the treatment provides maximum benefit.

After treatment, when will my tumor or lesion disappear?

The effects of radiosurgery occur gradually over a period of time. The time frame may range from days, months or even years depending on the medical condition targeted. Some tumors resolve more slowly than others and may or may not eventually disappear completely, while others simply stop growing and present no further biologic activity. After CyberKnife® treatments patients typically have periodic follow-up imaging examinations, such as CT, MRI or PET studies, as deemed appropriate by their medical team, to assess their progress. Laboratory tests may also be ordered.

Will my hair fall out or will my skin burn after CyberKnife® treatment?

The radiation delivered by the CyberKnife® is so focused on a specific target that it is highly unlikely that hair loss or skin burn will occur. In the event that a treated lesion is very close to the scalp or skin though, the adjacent hair or skin may be affected. If so affected, this hair or skin will typically recover over time. All medical procedures, including CyberKnife® treatment, have potential side effects and associated risks, and every patient will be individually evaluated and counseled in detail before a final plan of treatment is made. Any and all questions by the patient and their family will be answered before we proceed with treatment.

Is CyberKnife® covered by insurance?

Similar to other forms of radiotherapy and surgical treatment, stereotactic radiosurgery treatments, including CyberKnife®, are usually covered by Medicare and most private insurances. However, in some instances, CyberKnife may be viewed as a "new," "novel" or "unproven" treatment compared with existing "standard" treatments, and as such, may not be covered by insurance. If insurance denial occurs, our staff will work diligently to educate the insurance company and reverse their decision, though unfortunately, success in reversing their decision is not guaranteed.