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The CyberKnife® Robotic Radiosurgery System is a non-invasive alternative to surgery for the treatment of both cancerous and non-cancerous tumors anywhere in the body, including the prostate, lung, brain, spine, liver, pancreas and kidney. The treatment – which delivers beams of high dose radiation to tumors with extreme accuracy – offers new hope to patients worldwide.

Though its name may conjure images of scalpels and surgery, the CyberKnife® treatment involves no cutting. In fact, the CyberKnife® System is the world’s first and only robotic radiosurgery system designed to treat tumors throughout the body non-invasively. It provides a pain-free, non-surgical option for patients who have inoperable or surgically complex tumors, or who may be looking for an alternative to surgery.

The linear accelerator based radiosurgery machines are also prevalent throughout the world. One benefit of this technology is its ability to easily treat large tumor volumes (over 3.5 cm) by treating over several sessions. When treating over time, it is called fractionated stereotactic radiotherapy and not stereotactic radiosurgery (which is a one-session treatment). The machines are made by multiple manufacturers with common brand names: Novalis Tx®, CyberKnife®, and others. The Novalis Tx® is the most common machine available. Linear accelerator based machines are not dedicated to treatments only within the brain. They can be used throughout the body, as well as the head and neck.

Often, the linear accelerator radiosurgery unit must be set up before a treatment can be given. This occurs after all conventional radiation therapy is completed for the day. At centers where this is done, the number of radiosurgery treatments within the brain performed over a year is not usually high, and therefore, outcomes may not be as good. The linear accelerator based machines utilize one large intense radiation beam that is redirected in many "arcs" to lessen the adverse effects on healthy tissue. Since the linear accelerator moves during treatment, the degree of precision is less than that of cobalt-60 machines. These machines can perform radiosurgery on larger tumors and can fractionate treatments over several days, yielding a flexibility that is not available with other machines. Treatments that are given over time are referred to as fractionated stereotactic radiotherapy (FSR) or stereotactic radiotherapy (SRT). Because multiple manufacturers produce linear accelerator units, data and results are usually not comparable between different units and treating sites, as each type of unit requires different calibrations and adjustments. As a result, there may appear to be a lack of peer-reviewed research available about a diagnosis and treatment.

Stereotactic radiosurgery may or may not be appropriate for a condition. It may be used as the primary treatment or recommended in addition to other treatments that are needed. Only a treating neurosurgeon who operates radiosurgery equipment can make the evaluation as to whether someone can be treated. A neurosurgeon must always be present during treatment and should work with a radiation oncologist when the brain is being targeted. Some of the most common indications for treatment are:

Arteriovenous Malformations

All benign brain tumors including:

All Malignant Brain Tumors including:

Functional disorders including: