0:01

This was an individual who presented with left

0:04

sided vocal cord paralysis and hoarseness.

0:10

When you're looking for vocal cord paralysis,

0:12

you really have to follow the vagus nerve from

0:15

the skull base all the way down on

0:18

the left side to the aortic arch.

0:21

And because the recurrent laryngeal nerve goes

0:24

on the left side under the aortic arch,

0:26

and ascends in the tracheoesophageal

0:29

groove on the right side,

0:31

the vagus nerve comes down the carotid sheath,

0:33

and then the recurrent laryngeal nerve circles

0:36

the subclavian artery on the right side before

0:39

ascending in the tracheoesophageal groove.

0:42

So let's look and try to determine the

0:44

cause of this vocal cord paralysis.

0:47

So we would be starting in the brain and

0:49

then come to the jugular foramen.

0:52

And we don't see a tumor at the jugular foramen.

0:55

Here's the jugular vein,

0:59

here's the jugular vein.

1:02

But what we do see is a mass in the carotid

1:06

sheath and this mass in the carotid sheath is

1:10

likely affecting the vagus nerve and leading

1:13

to the vocal cord paralysis.

1:14

We see the manifestation of the vocal cord

1:16

paralysis by the medial deviation

1:20

of the cricoarytenoid joint,

1:22

by the enlargement of the laryngeal

1:25

ventricle on that side,

1:27

and by the atrophy of the vocal cord on the

1:32

left side compared to the right side.

1:34

So the volume of the vocal cord on the left side

1:36

is smaller because of long-standing vocal

1:39

cord paralysis leading to atrophy.

1:43

So now let's take a look at this.

1:45

So we see that this lesion is

1:47

enhancing pretty avidly.

1:49

It's a large lesion going to the skull base.

1:52

Well, which is it? Is it a schwannoma?

1:56

Is it a paraganglioma? If it's a paraganglioma,

1:59

is it a carotid body tumor or is it a glomus

2:04

vagale or is it a glomus jugulare?

2:06

So we mentioned that there was no involvement

2:08

or enlargement of the jugular foramen here.

2:12

This is the sigmoid sinus to jugular vein.

2:16

So the absence of involvement of the jugular

2:19

foramen argues against a glomus jugulare.

2:22

It's clear that the lesion is coming

2:24

up to the skull base.

2:25

However, the next thing that we can rely on is the

2:29

displacement of the external and internal

2:33

carotid artery at the carotid bifurcation for

2:36

determining whether or not this

2:38

is a carotid body tumor.

2:40

So if we follow the common carotid artery upward,

2:44

we see that there is some of this enhancing

2:46

tissue of the paraganglioma associated with it.

2:50

Here is the bifurcation.

2:52

You can follow this little piece of

2:53

calcification because that's going to be

2:56

associated with the internal carotid artery.

3:00

And here you see the external

3:03

carotid artery here.

3:05

So the carotid bifurcation with internal and

3:09

external carotid artery and both of them are

3:12

being displaced anteriorly by this mass.

3:17

And it is not at the carotid bifurcation per se.

3:22

It's not splaying the internal and external

3:25

artery at the bifurcation,

3:26

it's displacing it anteriorly.

3:30

And here's our jugular vein.

3:32

There is a little bit of thrombus

3:33

in the jugular vein,

3:34

but not a tumor in the jugular vein right there.

3:37

So maybe because it's being squashed by

3:40

the tumor. So based on this analysis,

3:42

we would say that this is most likely a glomus

3:45

Vagale tumor which occurs above the carotid

3:49

bifurcation at the angle of the mandible,

3:51

as we mentioned,

3:52

and that often goes to the skull base

3:55

at the C1, C2 level.

3:57

Let's look at this on the Sagittal plane because

4:00

maybe we'll be more convinced about

4:02

that carotid bifurcation issue.

4:05

Here is the internal carotid artery

4:10

draped anteriorly over the mass.

4:13

Remember that if it's a carotid bi tumor,

4:15

the internal carotid artery gets pushed

4:18

posteriorly, not anteriorly,

4:20

and the external carotid artery

4:22

gets pushed anteriorly.

4:24

We know that this is the internal carotid artery

4:26

because it has no branches in the neck.

4:28

And then we can follow it up to the

4:30

cavernous internal carotid artery.

4:32

So the anterior displacement of the internal

4:37

carotid artery argues that this represents a

4:40

glomus Vagale tumor which extends to the skull

4:44

base. The external carotid artery right here,

4:47

it too is in front of anterior to the tumor.

4:52

Hence, we have a nice example of a large glomus vagale

4:57

tumor causing vocal cord paralysis as it affects

5:01

the vagus nerve in the suprahyoid portion

5:05

of the neck carotid space lesion.