Image-guided radiotherapy uses imaging checks to confirm your position during treatment. It is often called IGRT.
The images are not taken to diagnose a new problem. They help the team make sure the treatment target is lined up as planned before the radiation dose is delivered.
Common Indications for Image-Guided Radiotherapy
IGRT may be used for:
- Prostate radiotherapy.
- Lung radiotherapy.
- Head and neck radiotherapy.
- Brain radiotherapy.
- Cervical or pelvic radiotherapy.
- SBRT or SRS treatment.
- Any treatment where small position changes matter.
What exactly does image guidance show?
It shows whether your body, bones, organs, or treatment target are in the right position for that session. The team compares the image with your planning scan.
How should I prepare?
Prepare the same way each day. If your team asks for a full bladder, empty bowel, or certain eating pattern, try to follow it consistently.
Do I need to stop taking medication?
Usually no. Keep taking your regular medicine unless your doctor gives another instruction.
What happens when I arrive?
The radiotherapy radiographers position you using your marks and supports. Then they take a quick image or scan while you are on the treatment couch.
How is image guidance performed?
The machine may take X-ray images, a cone-beam CT, or another setup image. If something is slightly off, the couch position can be adjusted before treatment begins.
How long does it take?
Image guidance adds a few minutes to the visit. The full session is still usually short.
Is there any discomfort?
No. The imaging check is painless. You just need to stay still while the team lines everything up.
Are there risks?
The imaging check may add a small amount of radiation. It is used because accurate positioning is important for safer treatment.
Why do I need images every day?
Small body changes can happen between sessions. Your bladder may be fuller, your bowel may be different, or your breathing may shift the target slightly. Daily checks help the team catch this.
Can I have IGRT if I am pregnant?
Pregnancy Precaution
Tell your doctor or radiotherapy team if you are pregnant or think you might be. IGRT is part of radiotherapy and may use extra imaging radiation, so pregnancy must be discussed.
Sources and further reading
- National Cancer Institute: External Beam Radiation Therapy, including image-guided treatment
- National Cancer Institute: Radiation Therapy to Treat Cancer
Conclusion
Image guidance is one of the quiet safety steps in modern radiotherapy. Your part is to arrive as prepared as possible each day, especially if your plan depends on bladder or bowel position.