0:00

And looks like people are getting the hang of things. So I'm gonna

0:05

go right to the next one, which is a penultimate case.

0:11

So this one, I'll give you some history.

0:14

We have, I'll say, a 54 year old male here. And I'm not sure if that's

0:19

the right age, but I think it's probably

0:23

reasonably relevant. And has a history of lymphoma and got a CT scan

0:29

and they saw some findings and they wanted an MRI. So I'm gonna

0:33

scroll through the T2 weighted images. And there's a lot of things going

0:39

on here, but what I want you to focus on is this thing.

0:42

And so as we go through the cases, I want you to look

0:45

at that lesion on all the different sequences. There are more lesions over

0:50

here, so... But this will be the dominant and representative lesion of

0:59

what we're gonna be talking about. So this is the T2 weighted image, T2

1:02

fat sat image. We can notice a signal.

1:05

It's not fluid bright, but it is relatively hyperintense. Let's look at

1:11

on the T1s in and out of phase. So just see if it

1:14

contains any fat. If it does, that's maybe relevant. If it doesn't,

1:18

we can toss that out. So you can see the out of phase image here, and the

1:21

in phase image here. All right. Then we're gonna move on to

1:28

our pre and post contrast sequences. So let me just lay it out

1:33

for the group over here. Pre and dynamic post contrast images.

1:39

Let's link everything. Let's zoom everything. And let's see if this works

1:46

for the scrolling. Let's see, you pull it down a little bit. Perfect.

1:49

Let's just focus on that lesion. So pre arterial,

1:57

portal venous, equilibrium phase images. Does the pattern of enhancement

2:01

help you? Is it irrelevant? Looks like it's enhancing. So that part of

2:07

it may not be as relevant, but does the pattern actually help you

2:09

in this instance? I'm not sure. And so that's... And I'll show you

2:17

some of the other nodules you can see here in the omentum. Those

2:21

are a little bit smaller. So it's harder to

2:24

figure out what we think is going on there.

2:27

And so once again, I'll just finish off with

2:31

perhaps one post contrast image and one T2 weighted sequence, just to show

2:36

you, give you another shot at figuring out what we think is going

2:41

on over here. All right. So let's have the question, question number nine

2:48

for this case, please. So this one, again, I'm not gonna jump to

2:52

what is most likely diagnosis. I'm assuming most of you have come up

2:56

with some options in your head, but I'm rather going to,

2:58

what is the next best step in evaluating this finding? And I'm presenting

3:03

to you very similar options to what was presented on a prior case.

3:07

And as I said, that's how I think about things. Sometimes do you

3:10

wanna put a needle in it, wanna do a PET/CT, which is another

3:13

imaging study. Do you wanna take it out surgery or do you wanna

3:16

essentially do nothing? Because you think you know what it is and you're

3:21

not worried about that. Okay, so most people wanna do nothing.

3:26

We have some options for a few other

3:31

things to do. Biopsy, surgery, PET/CT, patient has lymphoma. So PET/CT is

3:36

not an unreasonable thing to do, so you check the FDG avidity. Can we move

3:39

on to the next question? It'll be question number 10 for this case.

3:41

So now I'm gonna ask you, what do you think

3:45

this is? What is this? Is this indeed lymphoma? Could this be a desmoid

3:52

tumor? And we can talk a little bit about desmoids, but think about

3:57

what is desmoid associated with. Is that something that is relevant for

3:59

this case? The lesion horizon, liver focal nodular hyperplasia, could this

4:04

be that? And then splenosis. Another entity that can be seen in certain

4:13

clinical contexts. That's splenosis, very good. So a lot of people caught

4:18

onto this one, so I'm happy to hear that. And so in that

4:20

instance, if it's splenosis, and if you're sure about it, then not much

4:23

to do. I think we can make that diagnosis here. And so this

4:26

was a nice case. You look at... This patient does have lymphoma, had

4:31

a splenectomy for that history of lymphoma. And in the context of that,

4:38

I'm not sure what happened in the surgery, but there was

4:41

certainly deposition, it seems, of ectopic splenic tissue everywhere in

4:44

the peritoneal cavity. And so I'm just showing you representative vision,

4:46

but it is everywhere you look, and larger regions over here.

4:49

This one happens to be quite large. And the key thing,

4:52

at least with splenosis for MRI, is that it's gotta have signal that's similar

4:57

to spleen in all sequences. Now, that becomes difficult, admittedly, in

5:00

this case, because we don't have a spleen to compare it to.

5:03

But I think one of the key sequences here is the T2 fat sat, right? You

5:06

can see the bright signal that you'd expect from the spleen. But perhaps

5:09

the most important sequence here is the post contrast image, and I did

5:12

hover over that for a little bit. I'm sure a lot of you

5:14

caught on even before I hovered over it. Hey, look at that enhancement

5:18

pattern. There's not a lot of things that enhance like that in the

5:21

abdomen with the red pub, white pub differential enhancement, but then it

5:24

becomes more uniform on the remaining sequences. And so this was a case

5:29

of splenosis. We've done... We've been following this patient intermittently.

5:33

Nothing's been done, nothing of this is growing.

5:35

If you're confident in that diagnosis, you can say so, and you don't

5:38

have to do anything. And it's seen in the context of splenic rupture,

5:43

either traumatic or iatrogenic. It can occur anywhere, so always have your

5:46

guard up. My search pattern, if I don't see a spleen, then any

5:49

nodule may be a nodule of splenosis. So I always think about that

5:53

when I look at cases. But about two thirds of the time,

5:55

they'll occur somewhere in the abdomen and pelvis.

5:58

And if you're just not sure, if it doesn't quite match the imaging

6:01

sequence of the spleen, you can certainly biopsy, but before you do so,

6:06

consider getting a nuclear medicine study. The most sensitive and specific

6:10

one is the technetium 99m labeled heat denatured RBC scintigraphy. I don't

6:17

think they do a lot of that in many places, but I know

6:20

they can do it. So if you really need to know,

6:23

that's gonna be the best non invasive way to figure out whether it's

6:27

splenic tissue. So that's great. So I won't belabor that point because most

6:33

of you got that correct.