I also had an MRI, not the MRE. I swallowed some kind of tracer. I also had an eye scan before hand with an X-ray, I believe. Being an automotive worker put me at higher risk for metal slivers in my eyes. I saw 3D pictures of my guts and eyes on the doctors monitor when he showed me the plan before surgery. It was weird you could follow things as if you were inside it, if that makes any sense.