I have had both the MRI and CT Enterographies. They are similar except that the MRI is a much longer exam, almost 3 hours between the contrast being taken at 20 minute intervals and the amount of different postions for the imaging and the injection they give you to slow down the bowel motility midway through the imaging. You have to drink volumen for both tests- it's a contrast that looks opaque like semen but does not taste awful (in my opinion).
I believe that the only advantage to the MRI as a diagnostic tool is that it may enable slightly better imaging of bowel wall thickness. Bowel wall thickness is what determines the areas where inflammation is the worst.
Many patients reject the MRI and vomit during the procedure, (1) due to claustrophobia from being trapped in that tube for long periods, and (2) the glucaphen (I think that is what they call it) that they inject to slow down motility causes nausea and vomiting in 50% of patients, and they even have a vomit basin at the ready when they inject you. It did occur to me that if I vomited all over the inside of that tube and your daughter was next, I would hope they do a good cleaning before she gets inserted.
I was in the 50% that did not get sick. I didn't even feel any nausea. But it burned so badly going in that I screamed and totally freaked out the radiologist. She said, "what's wrong?????????????" And I said, "that shit feels like sulfuric acid going into my veins!!!!!!!!!!!" It only stung for a few seconds. My body didn't like it.
One other thing is that the MRI machine makes weird noises and sounds and the overall experience was like being in an alien spaceship, hostage to some unseen aliens conducting a noisy experiment.