Image Guided Radiotherapy (IGRT)
What is IGRT?
Image-guided radiation therapy (IGRT) uses imaging techniques to verify a tumour’s location/patient’s position before treatment to improve the precision and accuracy of the delivery of radiation treatment.
Tumour can move after each treatment session or during a radiation treatment session. Therefore imaging techniques are used for IGRT by visualizing bony or soft-tissue anatomy.
IGRT is used to treat tumors in areas of the body that are prone to movement, such as the lungs (affected by breathing), liver, pancreas, and prostate gland, as well as tumors located close to critical organs and tissues.
How does IGRT work?
Before the radiation beam is turned on, physicians use Image Guidance technology to provide precise and exact information on the specific location of any soft-tissue or bony target. This will allow delivery of treatment to a specific site/tumour while avoiding surrounding healthy tissues. That means less damage to healthy tissue, less “collateral damage.”
With most types of IGRT, the radiographers can take scans using the radiotherapy machine. This can be done before, during or after each treatment. This allows them to verify that the “target’ is within the planned treatment field. It is also used to ensure that the other organs have not “moved” into the treatment field especially the rectum and bladder in prostate radiotherapy.
What are the advantages of IGRT?
The main advantage of IGRT is that it is very precise.
It makes it possible to
- use higher doses of radiation to kill the cancer
- avoid harm to healthy tissue
- keep radiation side effects to a minimum
- ensures that the tumour is in the right position to avoid “missing the target”