Radiotherapy uses high-energy rays to treat cancer. It has to be aimed precisely to make sure exactly the right area of the body is treated each time. So when you have radiotherapy it’s important to be as still as possible.
If you have radiotherapy to the brain, head or neck area, you wear a radiotherapy mask to help you keep still. This is sometimes also called a mould, head shell or cast.
Once you are wearing the mask, it’s fixed to the radiotherapy treatment table. The mask holds your head and neck in exactly the right position. It will fit snugly but it should not be uncomfortable. You can breathe normally while you are wearing it. You only wear the mask while radiotherapy is being planned and during the treatment itself. You won’t have to wear the mask at any other time.