Intensity Modulated Radiation Therapy (IMRT)

Intensity-modulated radiation therapy (IMRT) is an advanced form of conformal radiation therapy delivered on a linear accelerator (treatment machine).

During IMRT treatment, the shielding that is built into the treatment machine moves while the radiation beam is turned on. This allows the amount of radiation dose coming from the treatment machine to be intentionally varied. By using many beams coming from different directions the radiation dose can be sculpted even more precisely to follow the shape of the tumour.

The benefit of IMRT is that the high-dose area is confined to the tumour volume more precisely and less of the surrounding area receives a high dose. This means the surrounding organs are better protected and the side effects of treatment can be reduced.

What is IMRT used for?

IMRT is particularly useful for tumours located near healthy organs that are sensitive to radiation therapy. IMRT can be an effective treatment for many types of cancer.

What does IMRT mean for you?

IMRT planning and treatment is technically demanding and requires a high level of precision.

For you as a patient this means having a planning computed tomography (CT) scan in the position of treatment. Extra equipment is likely to be used to help you stay in exactly the right spot. Developing the ideal radiation treatment plan for each patient can take a little longer depending on the complexity of the case. Precise quality assurance is also required to check the accuracy of the plan.

The IMRT procedure typically takes around 20 minutes, much like a three-dimensional conformal treatment. IMRT is used in conjunction with image-guided radiation therapy, where x-ray images are taken before treatment to ensure the highest accuracy of treatment delivery. IMRT uses the same type of radiation as other radiation therapy treatments.

The IMRT team

IMRT treatment is planned and delivered at all five of our Peter Mac radiation therapy sites: Melbourne, Bendigo, Box Hill, Moorabbin and Sunshine.

A team of specialists are required to plan and deliver IMRT, including radiation oncologists, radiation therapists and medical physicists. You will also be supported by a range of other professionals including nurses and allied health practitioners. The Peter Mac radiation therapy team is proud to offer this treatment, and we are dedicated to developing and progressing treatment options for the people of Victoria.

Please speak with your doctor to determine if IMRT is the appropriate treatment choice for you.