Write about the procedure involved in MRI.

It is a non invasive test used in medical field. MRI is very helpful in the diagnosis of cancers.
* MRI scanner is a big circular magnetic tube.
* MRI uses powerful magnetic field, radio frequency pulses and a computer to generate
images of internal organs.
* Each tissue has a different appearance on the film based on their water content.
* Sometimes a radiocontrast substance called gadolinium is used to increase the clarity of the image.