0:01

So this next patient is a 60-year-old male with

0:05

liver masses that they wanted us to evaluate on MR.

0:08

We weren't able to give contrast, but, uh,

0:10

there was an interesting finding in the gall

0:12

bladder that I thought was worth, uh, sharing.

0:15

And so we will, uh, start off with our

0:17

axial T2, uh, non-fat-saturated images.

0:20

There's a little bit of motion here.

0:22

We'll ignore the liver, which has very abnormal

0:24

signal that's brought about by the presence

0:26

of numerous, uh, masses within the liver.

0:30

We will focus on the gallbladder, though, as we

0:33

scroll downwards. You can see the gallbladder

0:37

over here. And I'll just sort of scroll through

0:39

at one time and scroll back upwards again and

0:42

just sort of focus, perhaps, on this slice. And one

0:46

of the things that I think looks a little bit

0:49

different about this gallbladder than some of the

0:52

other cases that we've seen is heterogeneous signal.

0:57

We know the gallbladder can have heterogeneous

0:59

signal depending on the concentration,

1:01

depending on the things, but the wall

1:04

of the gallbladder itself over here.

1:06

Now, we've seen cases of acute cholecystitis

1:08

where there is wall thickening, but that's

1:09

associated with hyperintense T2 signal,

1:13

which indicates edema and inflammatory change.

1:16

Certainly the wall is thickened here,

1:18

but the T2 signal is hypointense and

1:21

it's quite dark and it's circumferential.

1:24

And if we were to sort of look through all the

1:26

slices, you can appreciate that very discreet,

1:29

somewhat thick T2 hypointense signal that

1:32

surrounds the gallbladder in this instance.

1:35

Next up, I want to show you the T1 in

1:37

and out of phase images on this patient.

1:40

Over here is the T1 out-of-phase image, over here is

1:43

the T1 in-phase image, and there's a little bit of

1:46

motion here, but if we can just sort of see through

1:48

that area of motion and focus on the gallbladder

1:51

itself, there is some hyperintense T1 signal in

1:55

the gallbladder that just may reflect concentrated

1:58

bile and sludge, but I want to focus on the wall,

2:01

and again, we saw that it was relatively thick

2:04

on the T2-weighted images and quite hypointense.

2:07

Again, on the T1-weighted

2:08

images, it's relatively thick.

2:11

It is T1 hypointense as well.

2:13

And what happens on the out-of-phase

2:15

image versus the in-phase image?

2:17

On the in-phase image, you can see that the

2:20

wall appears even darker on the in-phase image.

2:23

And so when you see that finding, it's,

2:26

it's indicative, uh, and even on this medial

2:29

wall here, it looks a little bit darker.

2:31

Uh, it's another, it's a finding

2:33

that is indicative of potentially

2:35

calcium within the gallbladder wall itself.

2:38

T1 hypointense, T2 hypointense, blooms, uh, it

2:43

gets darker on the in-phase images over here.

2:45

And so when you have that circumferential

2:48

wall thickening, uh, gallbladder wall

2:51

thickening, which has that sort of signal,

2:53

gotta think about calcium within there.

2:55

And when you think about that, you have

2:57

to worry about porcelain gallbladder.

3:00

So this patient happens to have a CT scan that

3:03

was done, uh, prior to these images that I think

3:06

can very easily showcase that circumferential

3:11

calcification around the wall of a gallbladder.

3:13

And so this is a very good

3:15

appearance of porcelain gallbladder.

3:17

And why should we be worried about porcelain gallbladder?

3:21

Well, it's uncommon, so it's one of the

3:22

things that you should sort of know, but don't

3:24

expect that you're gonna see it every day.

3:27

Overall etiology, you know, there's lots of

3:29

theories, but suffice it to say that it's idiopathic.

3:32

We don't really know why the gallbladder wall

3:35

calcifies, and certainly ultrasound and CT are

3:37

the better imaging modalities to look at it.

3:39

MRI, it is quite challenging

3:40

to look for calcifications.

3:42

But these are the imaging findings,

3:43

should you be faced with it on any of your

3:45

cases, and why should we know about it?

3:48

Well, there is an association with an

3:51

increased risk of gallbladder cancer.

3:54

Now, in the past, that association was thought

3:57

to be maybe 20, 25 percent or quite high.

4:01

More recent data have suggested that the

4:02

association is still there, but it's a lot weaker.

4:04

Maybe 6 percent of patients with this rare finding

4:08

will end up harboring a gallbladder cancer.

4:11

And there is some data to suggest that perhaps the

4:14

risk of cancer is associated with the degree of

4:16

calcifications and that if you have more diffuse

4:19

calcifications, you're less likely to get it.

4:21

If it's more segmental or focal

4:23

calcifications, it does have an increased risk.

4:25

That data has not been substantiated.

4:27

However, the idea that this can be associated

4:31

with a small increased risk of gallbladder cancer

4:34

is out there in the literature, and that's one

4:35

of the reasons that it's important to know about

4:39

the imaging appearance of porcelain gallbladder.