0:01

All right, so we're going to go again

0:02

through the process of trying to evaluate

0:05

a full case here of Crohn's evaluation

0:08

and generating a report for this case.

0:10

And so in this case, the first thing we want to do,

0:13

as always, is detect any diseased segments.

0:16

And there's a real obvious area that we're going

0:19

to need to focus on in the right abdomen here.

0:22

You can see this Crohn's segment looks

0:24

like it has some sacculations in it.

0:26

There's some areas of narrowing and then

0:29

some areas of hyperenhancement on this

0:32

coronal post-contrast image.

0:34

Also, you can see that there's some

0:35

creeping fat here where there's a lot of

0:38

space between this loop of bowel and other

0:40

loops of bowel as that fat has become more

0:42

bulky, and there's some hyperproliferation

0:45

of the fat there, as well as a little bit

0:46

of vascular engorgement, arguably as well.

0:49

So for detection, we use that sequence,

0:52

and that was really all we saw.

0:54

We also want to use a T2 sequence.

0:56

In this case, I think that the axial

0:58

looks a little better than the coronal,

0:59

so we're going to use that to help us

1:01

with detection. And as we look through

1:04

here, we see those diseased segments again

1:06

over here, but we don't see any disease

1:09

particularly in the left abdomen jejunum.

1:11

Those old patterns look fairly normal and

1:13

the colon as well looks quite normal overall.

1:17

Similarly, we're going to look in

1:19

the same plane, but with contrast.

1:21

I always want to try to look

1:23

in two planes with contrast.

1:25

And here, again, we see similar

1:27

enhancement of the loop of bowel to the adjacent

1:30

loop of bowel in other areas of the abdomen.

1:33

So we're really focused just

1:35

on that ileal disease so far.

1:37

And lastly, we do look at our diffusion sequence,

1:40

and as we look through that, we see that diseased

1:43

areas are really bright, helping us detect those,

1:46

but the remaining portions of the abdomen,

1:50

the degree of diffusion restriction appears similar

1:52

throughout, and nothing that's jumping out at us

1:55

as being more impressive than other segments.

1:58

So, now that we've decided that the only

2:00

disease is in the right abdomen, we're

2:02

going to characterize that disease.

2:03

And here we're seeing at least two segments

2:08

that I think should be separately characterized.

2:09

So I'm going to measure the lengths of

2:10

both of those sequences because they're

2:13

both similar in degrees of inflammation.

2:15

I think we'll characterize them as

2:17

similar in terms of acute versus chronic.

2:20

And so we see some hyperenhancement

2:22

here, which suggests some acute changes.

2:25

We're going to want to compare

2:26

that to our seven-minute images.

2:27

And when we did that, it looks

2:30

very similar at seven minutes.

2:32

And so it didn't get a lot brighter, so

2:35

there's not a predominance of chronic changes.

2:37

We want to look at our T2 with fat

2:38

saturation, as we have here, and we see

2:41

that there are some edematous pieces here,

2:44

although it's not entirely edematous.

2:45

So there's definitely some acute changes here.

2:49

The presence of the sacculations indicates

2:51

there's also going to be some degree of

2:53

chronic changes, and then the creeping

2:55

fat is also a sign that there's

2:57

been significant disease for quite some time here.

3:00

There's an area of skipping here, so

3:03

oftentimes when it's a short segment of

3:05

skipping here, I'll actually give a general

3:07

idea of how much space is in between that.

3:10

Because in addition to evaluating the length,

3:13

the gastroenterologist just want to know if

3:16

they're going to be able to reach disease

3:18

segments when they do ileocolonoscopy.

3:20

So giving them a general idea of that,

3:22

I think is quite helpful when possible.

3:26

And then the next step is to evaluate for

3:29

any strictures or stricturing abnormalities.

3:33

And in this case, what we see

3:36

is the narrowing persists.

3:38

So there is a stricture.

3:39

We're going to want to measure the loops of

3:41

bowel in between, and here it's two centimeters.

3:44

So that's not too bad.

3:45

And here it is

3:47

three centimeters.

3:48

So that's a little bit more narrow there.

3:51

And so that would indicate

3:52

at least a mild stricture.

3:54

A more severe or moderate stricture would

3:57

tend to be four centimeters or more.

3:59

And then we want to evaluate for fistulas.

4:02

So as we look for fistulas, we want

4:05

to take a close look at any adjacent

4:08

loops of bowel that we may see.

4:11

And so when we do that, I don't see any

4:14

loops of bowel approaching this segment here.

4:17

And we need to do it on multiple planes.

4:19

However, with this segment, I

4:21

do see something that looks

4:23

suspicious, and it looks like

4:24

there's almost a T shape.

4:26

So importantly, bowel should

4:28

never have a Y or T shape.

4:30

And so if you see something that looks like that,

4:32

that should be a clue that something's amiss.

4:34

And that typically means that there's a fistula.

4:38

And so when we look at here and we

4:41

see this fistulization, we need to

4:45

characterize what's the bowel is going to.

4:47

And as we look a little more closely, we see

4:50

that the sigmoid colon is coming up through

4:52

here, and so the fistula communicates directly

4:55

with the sigmoid colon.

4:57

So we obviously need to fully

5:00

explain that and characterize that.

5:02

And as we look closely, we see that

5:05

there is a bit of inflammation involving

5:07

that portion of the sigmoid colon there.

5:10

And so that helps us give confidence

5:12

that there's clearly a fistula.

5:13

So we're going to put that

5:14

description into our report.

5:16

Anytime we see a fistula, we want

5:18

to look closely for abscess.

5:20

And so as we look at all of our sequences,

5:23

we don't see any fluid collections in the region.

5:26

Again, diffusion can be very helpful to identify

5:28

abscesses because typically abscesses centrally

5:31

do have a lot of restricted diffusion, and we

5:34

don't see any areas of diffusion restriction.

5:36

So in the end, what we're going to do is

5:38

characterize all the segments of disease.

5:41

So there's a disease segment here,

5:43

a disease segment here, and then potentially

5:47

a smaller disease segment here.

5:49

And so we'll give those lengths and those

5:51

distances and we'll characterize those.

5:53

We're going to say that there are fistulas, or there

5:56

is strictures; it's at least mild stricturing.

6:00

Given the presence of a fistula,

6:01

it could be moderate or severe, and you

6:03

wouldn't see the same degree of dilation,

6:04

but there is clearly some stricturing.

6:07

And then, we're going to say that there's

6:09

a fistula, and we're going to say the bowel

6:11

that it communicates with, which is

6:13

the terminal ileum and the sigmoid colon.