0:00

This was a case of a patient that presented with left-sided hearing loss and

0:04

facial nerve palsy.

0:05

And the key to making this diagnosis is that if you look at it,

0:09

you can see this mass right here that's involving the posterior portion of the

0:13

petre bone and actually has high T one signal.

0:16

And so if you have a lesion that has high T one signal and then when we give

0:20

contrast we can see that this is enhancing.

0:23

And the other thing that kind of tips us off about this case is when you look at

0:26

the heavily T two weighted image, and I think this shows it pretty nicely,

0:31

what we see here is expansion of the cortex overline, the left petre bone,

0:36

and it contains some this high T two signal. So if we look at the opposite side,

0:41

the center of this mass is actually located on the petris apex and it's actually

0:45

expanding the cortex. So if you see something like this,

0:49

especially if it's high T one signal and it's centered over the petre apex,

0:54

then this is pretty much uh,

0:55

what we say in the US and ant mini and the diagnosis here is gonna be endo

1:00

lymphatic sac tumors. So, uh,

1:03

any questions on that before I um, delve into endo lymphatic sac tumors?

1:09

So you guys are all experts in this.

1:11

So this is the classic appearance of an endo sac tumor. So these are benign,

1:16

uh, lesions, but they can be locally aggressive.

1:19

The mean age is about 22 years of age.

1:22

The symptoms are hearing loss tinnitus in vertigo and there is this associated

1:27

with von HIPPA Lindo.

1:28

So it's detected in about 11 to 16% of patients that have von HIPPA Lindo.

1:33

And about 30% are bilateral. So this is what I showed before.

1:37

If you see a mass here that's so located along the petre portion of the,

1:41

of the petre bone and it has high T one signal,

1:44

then you have to consider the diagnosis of endo lymphatic sac tumors.

1:48

Now on ct,

1:49

this is that classical expansile appearances sort of bubbly appearance that

1:54

arises from the posterior portion of the petre temporal bone.

1:57

And then when we look at the T two weighted images,

2:00

we'll see this low area of t one of T two signal.

2:05

And this is probably a combination of the expanded cortex that because they're

2:09

so vascular it probably represents some blood products as well too.

2:13

So that's why it,

2:14

you sort of get this heterogeneous appearance here with endo lymphatics act

2:17

tumors. Any questions at all on anything?

2:23

The,

2:24

for the case or anti end act tumor sometimes is

2:28

quite difficult to differentiate with, uh,

2:32

grow ja if the location is a bit more inferior,

2:37

right? So, so I can see the product and grow will be having,

2:40

the CT scan will be having the per bone erosion like this,

2:45

Right? Yeah. The thing is is that, and that's a great question.

2:48

The thing that that is,

2:49

is the following is that the endo lymphatic sac tumors typically are high signal

2:53

on T one weighted images.

2:55

So in general the gloma tumors that I've seen don't have this,

2:59

this high T one weighted signal.

3:01

The other thing about the endo lymphatic sac tumors that they involve the

3:03

posterior portion of the petri bone. Now if something gets really,

3:07

really big and it completely erodes everything, then you can't tell.

3:11

But remember, in fact, let me see if I can bring up this one case 'cause I just,

3:14

I just saw this case actually this morning, believe it or not.

3:19

So to answer your question in particular,

3:22

this is an example of a GLS jugular panicum tumor. Okay?

3:27

Now when we look at this, remember the, uh,

3:32

remember the endo lymphatic sac tumors were involving this portion here of the

3:36

Peter's bone. You see that Han?

3:39

Yes.

3:40

The posterior look exactly. Now look where this tumor is.

3:44

This is tumor involving the middle ear cavity.

3:46

And look what it's doing to the bone.

3:48

It's actually permeating the bone and extending inferiorly into the jugular

3:53

bone. So gloma tumors, at least when I look at these,

3:57

they tend to be more inferiorly located and unless they're

4:02

really, really big,

4:03

they tend to spare the posterior portion of the petre apex

4:08

posterior to the internal auditory canal. So that's how I differentiate.

4:12

End the lymphatic sac tumors from from Ggl,

4:15

jugular Jugulars or Ggl jug.