Image-guided Radiotherapy (IGRT)

What is IGRT? 

IGRT is a type of radiation therapy that uses detailed CT or MRI images taken before each treatment to narrowly target cancer tumors. It’s often combined with intensity-modulated radiotherapy, which varies the intensity of radiation beams so that stronger doses reach specific tumor areas. These therapies help Mercy cancer specialists treat tumors with greater precision, causing less damage to nearby healthy tissues.

How Does IGRT Work?

At the beginning of each radiation session, imaging scans are taken to precisely locate and measure your tumor. The same machine (or linear accelerator) that takes these scans also delivers your radiation. This real-time image guidance helps accurately aim radiation at cancer cells.

At your next treatment session, new scans are taken and compared with previous images to determine whether your tumor has changed position or size. 

Advantages of IGRT

IGRT is a treatment option with several advantages, including:

• Real-time monitoring of tumor position and size
• More targeted radiation shaped to tumors
• Higher-dose radiation delivery, potentially increasing treatment effectiveness
• Less radiation of healthy organs and tissues, reducing side effects and complications

What to Expect from IGRT Treatment

Your Mercy care team provides an outpatient treatment schedule, which typically includes daily treatments over six to seven weeks. Each treatment session lasts about an hour.

When you arrive for each session, you’ll be taken to the treatment room, where a Mercy radiation therapist will help you get positioned. You’ll most likely lie on your back, and the therapist may fit you with a device to help you remain still during treatment. Tiny markings may be made on your skin to line up equipment with the treatment area.

You’ll move through the machine once for pre-treatment imaging. Based on these images, your radiation plan or position may be adjusted. Then, you’ll move through the machine again slowly as customized radiation treatment is delivered.

IGRT is noninvasive and as painless as a CT scan or x-ray.

Side Effects & Risks of IGRT

IGRT can cause temporary side effects like nausea, fatigue or skin irritation. You may also have side effects in the area treated. For example, if your cancer is in your head, you may have headaches, hair loss or dry eyes.

Most side effects go away after treatment ends, but it’s possible to have long-lasting effects or experience them months or years later. Talk with your Mercy care team about potential side effects and ways to manage them.