Image-guided Radiotherapy (IGRT)

Image-guided radiotherapy (IGRT) is used together with three-dimensional conformal radiation therapy, intensity-modulated radiation therapy, and CyberKnife radiosurgery to improve the accuracy of each daily radiation treatment. In modern radiation therapy, accurate placement and shaping of the radiation beams is essential. IGRT uses special imaging technology, such as x-rays and cone beam CT (a compact, faster version of a regular CT that is attached to the linear accelerator and uses a cone-shaped x-ray beam), to take x-ray images before treatment to ensure the most accurate setup prior to treatment delivery. The radiation oncologist uses these images to adjust for daily changes in patient position and, in some cases, the normal shifting of organs within the body. Most patients benefit from this technology every day they receive treatment.