Image-Guided
Radiation Therapy (IGRT)

Image-guided Radiation Therapy (IGRT) uses imaging of the body both before and during the procedure to help guide the radiation with precision and accuracy to the exact area that is being treated. Radiation oncologists first perform a simulation to use as a baseline so that future images can be compared to it.

Using image guidance, fiducial markers can be placed in the body to pinpoint the exact area where treatment should be delivered. These can be small metal markers (about the size of a grain of rice) that are easily seen on imaging. Tattoos on the outside of the skin are also used in some cases. IGRT is used to treat cancers in areas of the body that are prone to movement, such as the lungs, liver, pancreas and prostate gland.

It is also used when the cancer is located near critical organs and tissues. CT scans, MRI’s ultrasound and x-rays can be used in conjunction with IGRT to help visualize soft tissue or bony anatomy.