0:01

So this entity that we're gonna discuss

0:03

right now, we've already talked about in

0:05

prior vignettes. This turned out to be a

0:08

primary neoplasm involving the right tonsil.

0:11

So here's our mass right here involving

0:12

the right tonsil, but the reason that I'm

0:15

showing this is for teaching purposes regarding

0:17

proper localization so we don't confuse this

0:21

disease entity involving the oropharynx

0:23

with another common lesion that can involve

0:26

this general area, which is a glomus tumor.

0:29

This mass right here was initially thought to be

0:31

a glomus tumor, specifically a glomus vagale tumor.

0:35

But I'm gonna explain to you the reason it's not.

0:38

So specifically when we look at this mass on

0:41

the non-contrast T1-weighted MR, we can see

0:43

the mass right here, and we can see the carotid

0:46

artery is displaced laterally. When we see a

0:49

lateral displacement of the carotid artery,

0:52

that tells us that the mass is not arising from the

0:55

location that a glomus tumor typically arises from.

0:58

Rather, it's arising from the visceral

1:00

space and typically arises from the tonsil.

1:03

So if I look at this image here on the top

1:06

left-hand side, there's our carotid artery.

1:09

If the carotid artery is displaced superiorly, that

1:12

means the tumor is arising from the carotid space.

1:15

If the carotid artery is displaced medially,

1:18

that means it's arising from the parotid gland.

1:21

If the carotid artery is displaced laterally, that

1:24

means it's arising from either the visceral space,

1:27

the retropharyngeal space, or the prevertebral space.

1:30

And if the carotid artery is displaced posteriorly,

1:33

that means it's arising from the parapharyngeal space.

1:36

So when we take that information,

1:39

and now we go back and analyze this MR. If we look

1:42

at the bottom right image on the T1-weighted

1:45

image with contrast with fat suppression, we can

1:48

see that the carotid artery is displaced laterally.

1:51

There's really maybe a few flow voids

1:53

right here, but really not a lot.

1:56

But the fact, if you're not sure, this lateral

1:58

displacement of the carotid artery confirms

2:00

that this mass is arising from the tonsil,

2:03

likely representing a primary malignancy of

2:05

the tonsil, typically squamous cell carcinoma

2:08

or lymphoma, and is not due to a glomus tumor.

2:11

Why that makes a difference?

2:12

Because if this was a glomus tumor, the

2:14

patients would have to undergo some type of

2:16

angiographic study and should not be biopsied.

2:19

If this was arising from the tonsil and is a

2:22

solid mass, then they can then perform a biopsy

2:25

and get the proper diagnosis and then

2:27

determine the proper course of management.