0:01

Okay, so here, for this case, what we have

0:03

is a pretty substantial case of ulcerative

0:06

colitis involving the rectosigmoid colon.

0:08

And what you'll notice immediately is that

0:11

there's a lot of enhancement of the colon here.

0:13

This is kind of the descending colon sigmoid junction.

0:16

It extends down into, throughout

0:19

the sigmoid and into the rectum.

0:21

All that inflammation goes all the way to the anus.

0:23

So this is a classic pattern, right?

0:25

You get inflammation extending

0:26

from the anus up into the colon.

0:28

It can go up higher than this, but it's confluent.

0:34

There's some other things to notice about this.

0:37

You get some of the vascular engorgement you'll see.

0:40

So the vessels are prominent as they

0:42

supply blood to this inflamed colon.

0:45

But what you don't see is a lot of inflammation

0:47

extending beyond the wall of the colon.

0:50

If you start seeing a lot of that,

0:52

you start to get more worried about

0:54

Crohn's disease, right?

0:57

You can have a little bit in this case, but

0:59

you don't have as much as a Crohn's case would.

1:02

Also on the T2 series, what you'll see is that

1:04

that outer wall oftentimes looks fairly normal as

1:08

compared to the mucosal and inner layers of the colon.

1:12

And that's another typical

1:15

appearance for ulcerative colitis.

1:17

Now, the reason you don't need to image patients

1:21

with UC routinely or as follow-up is because

1:24

you see patients with colonoscopy alone.

1:28

The reason imaging comes into play for a UC

1:30

patient like this is if they're contemplating

1:33

surgery or they're unsure of the diagnosis,

1:35

and they wonder if there could be Crohn's.

1:38

Because you don't want to do colectomies

1:39

typically that you would do for UC.

1:42

You don't want to do that in a Crohn's patient with

1:44

the pouch anastomosis because they're at high risk

1:47

for fistulas and complications with their pouch.

1:51

So what we need to really evaluate

1:53

is, yes, we see inflammation here.

1:55

They know that there's inflammation there.

1:56

They can see it on colonoscopy.

1:58

Are there other things that make

1:59

us think maybe this isn't UC?

2:01

So is there a fistula?

2:03

Is there an abscess or is there a skip

2:06

lesion and especially is the TI involved?

2:09

So give close scrutiny to the remaining bowel.

2:11

Make sure it's all normal as it is in this case.

2:14

And then you can say that this has a typical

2:17

appearance of ulcerative colitis and there's no

2:20

findings to suggest Crohn's disease on imaging.