“The magic power of X-rays and mysterious magnetic fields of the MRI”


I’m Matt and I am a CT radiographer in Derriford Hospital. In this brief piece I wanted to talk about a problem commonly encountered by the imaging team.

The majority of patients who are admitted to Derriford hospital will likely need some form of imaging and I have always strongly believed in trying to give the patient the best experience I can.

One thing that I have seen time and time again in the imaging department is a patient coming into the scan room scared, sad, angry and generally unhappy but then leave in a much happier state of mind. This isn’t down to the magic power of X-rays or the mysterious magnetic fields of MRI; it happens because of the great work by the imaging team.

A big obstacle commonly encountered are patients that are misinformed about the examination. I have had patients shouting at me before they have even entered the room saying ‘I am not going in that massive tunnel’ or ‘I can’t lie flat so I can’t have this scan’.  Straight away I have an agitated patient before I have even introduced myself.  Often patients arrive with incorrect information about what the examination is, which causes the patients to be stressed.

Outside of Radiology, unless you have already had an examination, it’s very easy to confuse what scan is what, and what each entails.

Allow me to describe the difference of two very common scan types

I will start with Computed Tomography (CT) scans, formerly know as CAT scans. CT scans use ionizing radiation with an X-ray tube rotating round the scanner very quickly. These scans usually take from 5-15 minutes and involve the patient lying on the scan table (not completely flat as they have a pillow and head support). The CT scanner is often described as a doughnut shape or a polo mint.

With these scans it is likely the patient has an injection of iodine based X-ray contrast which will make them feel hot and feel like they are passing water (sounds wonderful I know).  Unlike MRI, the patient will not get headphones or listen to music, as the scans are much quicker and quieter.


Magnetic Resonance Imaging (MRI) is often mistaken for CT, and vice versa. MRI scans do not use any form of radiation, and is a large tube that contains powerful magnets.  MRI scans use strong magnetic fields and radio waves to produce very detailed images of inside the body.  The scanners themselves are described as tunnels. You get headphones with music to listen to and these scans last up to an hour.  You can also have a contrast injection with MRI but this is very different and not iodine based.

Reading this you might be thinking, “What’s he fussing about?”

The scans are very similar, but for patients with severe claustrophobia thinking they have to go into a long tunnel rather than just a simple doughnut or young patients horrified of being subject to radiation, these differences are a big deal.

Informing our patients correctly before they arrive for the examination not only helps the Radiographers, perhaps more importantly the patients.

Matt Lamerton



Matt is writing as part of the #WeCare2 campaign that will be running across our Trust communications. Look out for more from Imaging, and their AHP and HCS colleagues, on our social media pages, Trust screensavers, Daily Email, Vital Signs and much more.

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