Stereotactic Radiation Therapy

EvergreenHealth's advanced Varian Trilogy® linear accelerator is also able to provide an external beam radiation therapy called stereotactic radiation.

It uses focused radiation beams to treat very small, well defined tumors or abnormalities with surgical-like precision.


How Does Stereotactic Radiation Work?

It begins with detailed imaging of the tumor done by both MRI and the GE wide-bore CT Simulator. 

These images are fused together and a dedicated computerized 3-dimensional treatment plan using the Brain Lab system is created to deliver the radiation dosage precisely to the tumor.

Prior to the treatment, the Trilogy's onboard imaging system - both standard X-rays and CT scans - is used to make sure the patient is perfectly aligned with the treatment plan before the radiation beams are fired.

With the high dosage of radiation given, it is critical to know that the target is absolutely spot on.

Most patients will require just one treatment, with minimal discomfort and little or no side effects.


Patient Comfort

Another bonus of EvergreenHealth's stereotactic radiosurgery is patient comfort.

Other systems, like the Gamma Knife, require an invasive procedure where screws are drilled into the patient's skull in order to attach the ring which holds the head rigidly still during treatment.

This is not necessary with EvergreenHealth's Varian Trilogy technology. 

Instead, each patient is fitted with a custom head and face mask. The mask is put in warm water and then fitted to the patient's head for a perfect fit.

The mask is anchored to the treatment table, holding the patient still - and comfortable - for the treatment.


Types of Stereotactic Radiation Therapy

There are two types of stereotactic radiation therapy:

Stereotactic radiosurgery, which involves delivering stereotactic radiation treatments to the brain or spine.

This is done by a team involving a radiation oncologist and a neurosurgeon.

It is typically used for:

  • Cancers that start in the brain (gliomas and other primary brain tumors) 
  • Cancers that spread to the brain (brain metastases) 
  • Benign tumors arising from the membranes covering the brain (meningiomas) 
  • Benign tumors of the inner ear (acoustic neuromas).
  • Abnormal blood vessels in the brain (arteriovenous malformations or AVMs)

Stereotactic body radiation therapy involves delivering stereotactic radiation treatments to all sites within the body, except for the brain or spine. 

This treatment is delivered by a radiation oncologist.

It is typically used for:

  • Small tumors in the chest, abdomen or pelvis that cannot be removed surgically or treated with conventional radiation therapy
  • Small lung cancers
  • Cancers that started elsewhere and spread to the lung (lung metastases)
  • Cancers that started elsewhere and spread to the liver (liver metastases)

Stereotactic radiation may be useful for other cancers not readily addressed with surgery or conventional radiation therapy.


For More Information

To learn more, or to schedule an appointment, call Halvorson Cancer Center Radiation Oncology at 425.899.1860