Linear Accelerator

The Varian True Beam linear accelerator is one of the safest and most powerful systems available.  This cutting-edge technology can treat all parts and organs of the body with a uniform dose of high-energy x-ray to destroy the cancer cells while blocking the radiation field from reaching the normal tissue during treatment.

The linear accelerator is used during external beam radiation therapy.  The patient lies on the moveable treatment couch while the machine‚Äôs lasers ensure the patient is in the proper position.  The treatment couch can move in a variety of directions so the radiation can be delivered to the tumor from any angle.  Tumors can move during treatment (usually due to patient respiration) and between treatments (usually due to day-to-day variations in patient setup).  Dynamic Targeting IGRT from Varian Medical Systems offers clinicians advanced imaging techniques to verify patient position and tumor position at the time of treatment.

The radiation oncologist will prescribe the appropriate treatment volume and dosage, and the radiation therapist operates the linear accelerator from an adjoining room with a closed-circuit monitor and microphone, so the patient and health care professional can communicate during treatment.

Dynamic Targeting IGRT translates into faster outpatient treatments, greater patient comfort, and the potential for better outcomes and fewer side effects.


Tissues, organs, and many tumors are not rigidly fixed in one position; they move around inside the body due to natural physiological processes.  For this reason, they are not always in the exact same position each time a patient is positioned for treatment.  In addition, tumors can move several centimeters due to a patient's normal respiratory cycle.

For Dynamic Targeting IGRT, the medical linear accelerator, or treatment machine, is outfitted with a number of sophisticated imaging devices that provide the clinician with images that help to guide the treatment.

An X-ray system mounted on a robotic arm is rotated around the body to gather images that pinpoint a tumor's exact location just prior to treatment.  These images are then compared with reference images (MRI, CT or other kinds of scans) in order to determine if the tumor is where it is expected to be, or off by some margin.  Sophisticated software programs calculate how to move the patient so that the tumor is directly in the center of the treatment beam.


Over 60% of cancer patients receive some form of radiotherapy as part of their treatment.  This is because radiotherapy is very effective at controlling many forms of cancer by destroying the cancer cell's ability to reproduce.

Through more precise targeting of the beam, dosage levels can be increased and target volumes (the three-dimensional areas to receive treatment) can be reduced - so tumors get a higher dose of radiation and healthy surrounding tissues get very little.

Imaging and tracking technologies that are used in delivering IGRT enable doctors to treat tumors even if they are close to vital structures like the spinal column, salivary glands, heart, or lungs.  This can mean substantially fewer side effects and a much better post-treatment quality of life.


Dynamic Targeting IGRT is an advanced and versatile cancer treatment that can enhance radiotherapy treatment precision and allow physicians to escalate the radiation dose to cancer cells while keeping the dose to surrounding tissues a low as possible.  This increases the chances of eradicating the tumor and minimizing treatment side effects.

Dynamic Targeting IGRT offers physicians imaging techniques to verify patient position and tumor position at the time of treatment.