The MRI machine is very noisy, but it is a painless test and does not expose you to any radiation. If you are clausturphobic, you may want to get medication to take before hand, because you will be partially enclosed.
Assuming you have no metal in your body, you're safe. The only other possible danger is a reaction to the contrast material, which the doctor might not even need to use. You'll just lie still in a machine for half an hour or so while it makes loud noises.
MRI's can be open or closed machines. Open machines are used for the obese and those with fear of enclosure. One cannot have any metal on during the procedure and questions will be asked before the procedure. Some people whom have had previous surgeries cannot have MRI's. MRI's are loud.
