0:01

So this is a seven-year-old male

0:02

with right upper quadrant pain.

0:04

He has an MRI for further evaluation of these findings.

0:09

We'll start off with the T2 non-fat-saturated

0:11

image, scroll through it one time,

0:15

and there's a lot of stuff going on here.

0:17

But I just want to focus on one particular aspect of

0:22

this one abnormality in this patient, and that is going

0:24

to be the finding we see in Morrison's pouch over here.

0:28

So right over here, I'm going to zoom up on it.

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And we'll scroll through this up and down.

0:33

It looks like there is a relatively

0:36

discrete collection over here.

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Internally, it has heterogeneous signal intensity.

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A lot of it is T2 hyperintense, but you

0:44

have these T2 hypointense content as well.

0:49

And some of them again have

0:50

that geographic shape, right?

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Rounded borders, relatively sharp borders.

0:55

The liver surrounding it also has

0:57

that sort of intermediate inflammatory

0:59

T2 signal associated with it.

1:01

So, uh, something that we need to pay attention to.

1:05

We'll look at the T1 pre-contrast image to start,

1:09

and you can already see that there is this T1

1:12

hypointense finding, relatively discrete, uh, just

1:17

a little bit more cephalic to where we've been, uh,

1:19

showing the epicenter of what's going on over here.

1:22

But as we go to that location, you can see

1:24

that there are multiple T1 hypointense

1:27

filling defects within this thick-rimmed collection

1:32

that we see here, and a large one over here as well.

1:35

And so again, we have a case where we have what looks like a

1:39

collection with content that is T1 and T2 hypointense.

1:45

When we give contrast, we can see that this collection

1:49

has a thick rim enhancement associated with it.

1:53

And on different phases of the contrast, we can see some

1:57

of that inflammatory change become a lot more apparent.

2:00

And this happens to be a patient who is also post-

2:03

cholecystectomy, and we're seeing an abscess essentially

2:07

in Morrison's pouch containing content that is T1

2:10

and T2 hypointense with a relatively geographic shape.

2:14

Uh, the top thing on the differential would have to

2:17

be dropped gallstones with an associated abscess.

2:21

And, uh, this is indeed what the patient had.

2:24

And just to show you, in this particular patient,

2:28

the scan from several years prior, as we scroll

2:31

downwards, we can see that there's that one calcified

2:34

gallstone in that location, and a whole cluster

2:39

of calcified gallstones seen in Morrison's pouch.

2:43

And so the first case of dropped

2:44

gallstones we saw was for non-calcified

2:47

gallstones associated with an abscess.

2:49

In this one, we have calcified gallstones

2:51

that over time developed an abscess.

2:54

And for these, uh, particularly when they're of

2:57

this size, that have developed and are causing

3:00

symptoms, you know, these would need to be removed.

3:03

So dropped gallstones in and of

3:04

itself are very symptomatic.

3:06

You don't need to do anything about it.

3:08

Once complications develop, uh, they need to be fixed.

3:11

So the abscesses need to be drained,

3:13

and the nidus causing all that infection

3:16

and complication, which is the gallstones

3:18

themselves, would also need to be removed.