How do a pet scan and a mri scan differ?

See below: An MRI or magnetic resonance imaging is a study that provides anatomical description of a part of your body. A pet scan can provide further information aside from how it looks or appears. It utilizes radioactive material or tracers that see how cells in your body function. It can detect cancer cells not evident on MRI or ct, heart disease, infection and even neurological conditions like dementia.

Anatomy vs Physiolog: Mri and ct look at the structure of the body, the anatomy, and the way diseases change or distort it. Pet looks at the physiology, or how the body uses, or metabolizes something. For pet, the most common metabolism pathway looked at is how glucose is used.

Radiation...: Mri does not give the patient radiation dose. Pet/ct gives radiation dose from both the radiotracer injection and the ct portion. Pet, ct, and MRI all have their own advantages and disadvantages and can be complimentary tests when they are all used together. Pet/ct shows function (glucose utilization) and anatomy while MRI shows anatomy. Currently pet/mri is being developed as well.