Question: how does the radiation on the brain work? on the video i mean.

Rob Brass answered on 13 Jun 2016:

Hi Connor!

It’s a pretty cool video isn’t it! It was filmed by a patient in America, he strapped his GoPro camera onto the machine!

I don’t know the exact details of his treatment but I can explain in general 🙂 So cancer is just a group of abnormal, rapidly dividing cells. It happens when the DNA of cells gets damaged in some way (through UV radiation from the sun, smoking, etc.) but instead of killing the cell it just causes it to go a bit haywire!

When we deliver radiation to a patient it interacts in the body and kills the cells in its path. By aiming the beam at the tumour and avoiding healthy bits we can make sure we kill a lot more tumour cells than healthy cells! So the aim of radiotherapy is exactly that: to give enough radiation to the tumour to kill it while trying not to give too much radiation to the healthy organs around it.

Also, we tend to give most radiotherapy in small daily treatments (called fractions) over several weeks, by doing this it gives the healthy cells time to recover. The tumour cells recover more slowly as they aren’t proper functioning cells.

The man in the video is receiving treatment for a brain tumour. A ‘plan’ will have been made using special software that tells the machine what to do. The mask he’s wearing is clipped onto the treatment bed so that he cant move. This is important as we need to make sure we’re aiming the beam where we need to otherwise we could cause a lot of damage! The arms coming out the side of the machine are actually to take x-rays! One of them delivers the x-ray and the other is the detector, we see these pictures straight away (no more old school x-ray film!) and they help us to make sure he’s in the right place.

He then get’s treated according to the plan that was made for him. The treatment bed will be moved to where it’s supposed to be and then the plan will be loaded, this tells the linac which angle to rotate to, what size field is needed, how much radiation to deliver, etc.

As I said we treat our patients every day for several weeks, so he’ll be back the next day and go through exactly he same process of being clipped into his mask, having x-rays taken and then treated.

Is that ok? I’ve tried to keep it general but if you want a bit more detail on anything just comment back! 🙂

Cheers!