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Question 32.21: An MRI scan might be considered a safer procedure than a CT ...

An MRI scan might be considered a safer procedure than a CT scan.

a Explain why it might be considered to be safer.

b Why might a CT scan be chosen in preference to an MRI scan?

c Explain why MRI is described as non-invasive

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a MRI uses non-ionising RF electromagnetic radiation, whereas CAT scanning uses X-rays, which are a form of ionising radiation.
b CAT scans show up bone, which is poorly imaged by MRI.
c The patient’s body does not have to be cut open, nor do any instruments have to be inserted into the body

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