Image Guided Radiation Therapy (IGRT)

Sometimes tumors of certain types of cancer can move slightly between radiation treatment visits because of difference in organ filling or movement while breathing.  With image guided radiation therapy, or IGRT, your radiation oncologist uses imaging from a CT scan, ultrasound or X-rays to better target tumors that may have moved, while avoiding nearby healthy tissue.

With IGRT, all patients first undergo a CT scan as part of the planning process.  Just before each daily radiation treatment, additional imaging is taken in the treatment room using either CT, ultrasound or X-ray.

The information from the most recent scan is then transmitted to a computer in the treatment room to allow doctors to compare it to the earlier image . During IGRT, doctors compare these images to see if the treatment needs to be adjusted. In some cases, doctors will implant a tiny marker in or near the tumor to pinpoint it for IGRT. This helps to account for organ/tumor motion even if the body is immobilized by a casting device.