0:01

So, this patient is a 60-year-old male.

0:03

History was assessed for choledocholithiasis.

0:05

So we got an MRI of the abdomen with an MRCP sequence.

0:09

And so let's scroll down and focus

0:11

on the gallbladder over here.

0:13

As we scroll through these images, we'll start

0:15

off with an axial T2 non-fat saturated image.

0:21

And let's just scroll completely

0:22

through the gallbladder to get a

0:24

big picture view of what's going on.

0:28

And really the big picture view is that

0:30

the gallbladder doesn't look very happy over here.

0:33

A little bit distended.

0:34

We see some gallstones lying deeply

0:37

in these T2 hypointense structures over here.

0:39

We see a lot of gallbladder sludge

0:41

as well, occupying most of the

0:42

gallbladder, and surrounding the gallbladder

0:46

there's just a lot of inflammatory change as well.

0:49

There's wall thickening as well, but I want to draw

0:51

your attention to this group of this sort of abnormality in

0:52

that non-dependent portion of the gallbladder.

0:56

So we can look at it and see if there

0:59

are discrete T2 hypointense structures.

1:01

Here that are within the non-dependent

1:03

portion of the gallbladder. To be honest, it's

1:06

very difficult to even know where these are

1:08

located. We can see that the gallbladder wall is

1:10

somewhere in this location. So it's possible

1:13

that they're in the gallbladder wall itself.

1:17

It's possible.

1:17

Some of them are outside of the gallbladder wall.

1:20

There's a lot of fluid in this location, and so that

1:24

appearance is a little bit unusual. Let's look at the

1:28

same finding on our T2 fat-saturated images to get

1:33

a better sense of what everything looks like.

1:36

You can see a lot of inflammatory change,

1:38

this sort of intermediate to hyperintense

1:40

T2 signal within the gallbladder.

1:42

We can see the gallstones lying dependently, but

1:44

we also see a cluster of T2 hypointense foci that

1:48

are non-dependent. Some of them may be in the

1:51

gallbladder wall lumen, but a lot of them look like

1:53

they're potentially in the wall of the gallbladder.

1:56

We have an oblique T2 image as well.

1:58

Again, just to show you these findings, I'll just

2:02

window this a little bit so you can see nicely what

2:04

these non-dependent filling defects look like.

2:08

And then certainly in this instance, they look

2:10

like they're outside of the gallbladder wall lumen.

2:13

This is the wall of the gallbladder

2:14

itself, right over here.

2:16

And this is located, at least the epicenter

2:20

of this, is within the gallbladder

2:21

wall.

2:23

I'll finally show you these sets of sequences.

2:25

This is the in-and-out.

2:26

I usually don't use these a lot to

2:28

evaluate for gallbladder abnormalities.

2:30

In this instance, I think it's something

2:32

that becomes somewhat useful.

2:36

So here we have, over here, a T1 out-of-phase sequence.

2:42

Here we have the T1 in-phase sequence.

2:45

We can see that cluster of abnormality

2:49

in the non-dependent surface of the gallbladder

2:52

being hypointense on both sets of sequences.

2:56

On the in-phase sequence, we can actually

2:57

see that it is more hypointense.

2:59

In fact, there's some blooming

3:00

artifact associated with this.

3:02

And so putting this all together, we have

3:04

a gallbladder that looks inflamed within

3:06

the non-dependent portion of it.

3:09

In the wall, there is a cluster of

3:11

findings that are T1 and T2 hypointense.

3:15

And on the in-phase T1 with

3:17

images, these findings bloom.

3:19

So this should make one worried about the presence of

3:25

gas within the gallbladder wall itself, and this indeed

3:27

is air within the gallbladder wall, and it's a case

3:30

of emphysematous cholecystitis, another more advanced

3:34

form of cholecystitis, and it's quite uncommon.

3:38

It's due to the presence of gas-forming

3:40

organisms, such as some Clostridium organisms, E.

3:44

coli as well can do it.

3:46

Often, patients who get these have a history

3:48

of diabetes, and it is considered a surgical

3:51

emergency because of the high mortality rates that

3:55

are associated with emphysematous cholecystitis.

3:58

The key thing that you're going to look for is the

4:00

presence of gas within the gallbladder wall itself.

4:05

Oftentimes, this should be picked up on ultrasound.

4:08

If it's unclear on ultrasound, a CT

4:10

scan is very good to pick up gas.

4:13

MRI should really not be used to evaluate for

4:15

the presence of emphysematous cholecystitis,

4:17

but as you can see in this instance, this

4:20

was a case where we picked it up on MRI.

4:22

The key thing is that gas itself will be hypo

4:26

intense on all imaging sequences, and on the in

4:28

phase sequence, we'll have that blooming artifact.

4:31

When you see that, you've got to be worried about gas.

4:32

If it's in the wall, you've got to be

4:34

worried about emphysematous cholecystitis.