0:01

So, for this case, we're going to show some

0:03

normal anatomy and how the sequences should look

0:06

on a normal patient without any inflammation.

0:08

And so, starting with the TrueFISP sequence here,

0:11

you can really see well that the jejunum in the left

0:14

upper quadrant has relatively thicker folds compared

0:18

to the ileum in the lower abdomen on this case.

0:22

And that's typically what we're going to see.

0:24

You know, the jejunum has those thicker folds

0:26

and does more of the absorption of nutrients.

0:28

And so, that's what you expect to see.

0:31

Now, when I'm reading cases with fellows,

0:33

the number one mistake that I see beginning fellows

0:36

and later residents make is they want to call

0:39

this out, this difference in thickening,

0:41

they want to call that inflammation or bowel pathology.

0:45

And you've got to be very careful to understand that

0:47

this is normal anatomy, that you expect to see that

0:50

you can see it here on this TrueFISP sequence

0:53

and to some extent on the T2 sequence as well.

0:57

The place where residents often get confused

0:59

is when they look at the post-contrast images.

1:01

And that's because, look how much it looks like

1:04

this jejunum is enhancing more than the ileum.

1:06

But that's just expected and normal because of

1:09

the slightly thicker wall. You get a little more

1:11

gadolinium, and it looks like it's enhancing more.

1:14

So, when you do your evaluation of

1:16

bowel hyperenhancement, you have

1:18

to compare to similar loops of bowel.

1:21

So, if you're going to compare a loop of

1:22

jejunum and say that it's hyperenhancing,

1:25

you want to compare it to adjacent loops.

1:27

Unless it's markedly thickened diffusely,

1:29

which you rarely, rarely see.

1:32

That's the right way to evaluate these cases.

1:34

As we look at the ileum, you see that

1:37

as you get more and more distal, you see

1:40

a little bit less and less enhancement.

1:41

So, comparing to segments of bowel that are relatively

1:44

close in proximity is going to be important to

1:47

really making sure that when you evaluate Crohn's

1:49

disease, you're doing it the right way.