0:01

Next patient is a 45-year-old female who

0:03

presents with right upper quadrant pain.

0:06

And so we got an, uh, an MRI to

0:09

evaluate some of these findings.

0:11

And in this instance, I'll start off by

0:13

going on the T2-weighted fat-saturated image.

0:17

And so, as with a lot of the patients

0:19

we've seen in this course, there's a

0:21

lot of other abnormalities going on.

0:22

We're going to try to ignore all that.

0:24

And I want you to focus on the abnormality

0:28

seen in Morrison's pouch over here.

0:32

Now this looks somewhat familiar to, um,

0:34

some of the things we've seen already.

0:36

We have, uh, looks like a collection over here.

0:39

It's T2 hyperintense.

0:41

Inside of it, we have these filling defects.

0:43

This happens to be a round one.

0:45

Many of them happen to be round.

0:46

Some of them have more sharp and geographic

0:48

borders that are associated with it.

0:51

Um, and so this is another patient

0:53

who's had a cholecystectomy.

0:54

And so we see this imaging appearance of

0:57

a collection in this location containing

1:00

what really does look like gallstones.

1:01

We have to be worried about dropped

1:03

gallstones and the associated abscess.

1:05

We can look on the post-contrast image.

1:08

The rim of this abscess is enhancing quite avidly.

1:12

The filling defects themselves are hypointense

1:15

on the T1-weighted images, as we would expect for

1:17

cholesterol gallstones, which are the more common

1:21

type of gallstones we see in the United States.

1:25

And so, again, this is another case of

1:26

dropped gallstones and associated abscess.

1:28

I want to show a bunch of these cases so you're

1:30

used to sort of looking at this imaging appearance.

1:32

One of the reasons I also wanted to show this

1:35

case is that we often don't do diffusion-weighted

1:38

imaging in our institution, but I know, uh, that

1:41

there are other places that do it more often.

1:43

And so if your institution does do them,

1:46

I wanted to just show you what this would

1:48

look like on diffusion-weighted imaging.

1:50

So we have several B values here: B50, 400, and 800.

1:55

You can see that there is hyperintense

1:59

signal on the high B value images over here.

2:02

And, uh, on the ADC images, we can

2:04

see that it is hypointense signal.

2:07

So this is restricted diffusion within

2:10

this abscess as we would expect to find.

2:14

Uh, and in this instance, this abscess was a result

2:17

of dropped gallstones in, uh, Morrison's pouch.