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When we think of the various vasculopathies of the

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carotid space or vascular lesions of the carotid space,

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there is one normal variant that I'd like to point out.

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Here we have unilateral medial deviation of the

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carotid artery into the retropharyngeal space.

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Retropharyngeal space is defined by the retropharyngeal

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fat which you see as the bright signal

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intensity on the T1-weighted scan.

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And although we have the carotid artery and jugular vein

0:30

on the left side well seen we only see the jugular vein

0:34

here on the right side with this medial

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deviation of the carotid artery.

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That is a normal variant and it's due to the relative

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incompetence of the pretracheal the middle layer of the

0:49

deep cervical fascia which allows the

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carotid artery to migrate medially.

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As you can see on this section through the CT scan we

0:58

have bilateral internal carotid or common carotid artery

1:03

medial deviation into the retropharyngeal space.

1:07

This is an important normal variation in one particular

1:11

setting and that is when the surgeons are contemplating

1:15

an anterior fusion of the cervical spine.

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With an anterior fusion they're coming in through the

1:22

retropharyngeal space and prevertebral space to get

1:26

to the anterior portion of the vertebral body.

1:30

And the presence of the internal carotid artery in this

1:34

medial location could be disastrous if they're not

1:38

expecting it because they could injure either of these

1:41

carotid arteries on their approach to do a fusion

1:46

anterior fusion of the cervical spine.

1:48

This medial deviation of the carotid

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artery is transient.

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You may see within a single MRI scan in one setting,

1:57

you might see the carotid artery medial but in the next

2:00

setting, it may be back to its normal location.

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It's that transient.

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And this has been described by Bruce Wasserman

2:07

in his reports on the carotid artery.

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But if we go on to true pathology of the carotid space

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looking at intrinsic vascular disease probably the most

2:20

common of the intrinsic vasculopathies of the carotid

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space is going to be fibromuscular dysplasia.

2:28

Fibromuscular dysplasia on imaging.

2:30

As you see in this carotid arteriogram is typified by

2:34

areas of narrowing and widening of the vessels be it the

2:40

carotid arteries or the vertebral arteries in the neck.

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Most commonly,

2:46

it's going to involve the internal carotid arteries.

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However,

2:48

it may also involve the common carotid arteries

2:52

and as I said previously, vertebral arteries.

2:56

You may also see it involving

2:58

the external carotid artery.

2:59

And this typical beaded shape

3:03

identified by areas of narrowing followed by areas of

3:08

widening and that little kind of quirkscrew look

3:11

to it is typical of fibromuscular dysplasia.

3:16

And this may lead to carotid dissections.

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And in this case,

3:20

an example of a carotid dissection leading to a

3:24

cavernous rotted fistula secondary to the dissection

3:28

into the cavernous sinus fibromuscular dysplasia,

3:32

the most common of the vasculopathies of the carotid

3:36

artery that are primary to the carotid space.

3:41

I mentioned previously the fact that we have a high rate

3:45

of seeing cases of Loeys-Dietz syndrome at Johns

3:50

Hopkins because Hal Dietz attracts these

3:53

patients and evaluates them.

3:55

This is a type of vasculopathy or type of connective

4:00

tissue disorder analogous to Marfan syndrome.

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And as you can see by this article that was written

4:07

by one of my research fellows, Vanita Rodriguez,

4:12

along with Loeys and Dietz,

4:15

with me being the senior author on this paper.

4:18

The Loeys-Dietz syndrome is described as showing the

4:22

triad of arterial tortuosity and aneurysms

4:26

hypertelorism and bifid uvula, or palate.

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So that hypertelorism and bifid uvula and palate

4:34

distinguishes it from Marfan syndrome which obviously

4:37

has a lot of the manifestations of the vascular disease.

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However, has other manifestations,

4:43

that being the lens dislocations and the elongated

4:48

vertebral bodies and large size.

4:51

So we looked at some of the patients who had

4:55

Loeys-Dietz syndrome, in this case, 25,

4:57

that had head and neck CT scans and MRI scans and what

5:02

we found was indeed torturous blood vessels which are

5:06

seen in this three-dimensional reconstruction

5:08

of the CTA in this individual.

5:11

Notice the corkscrew-like appearance of the internal

5:15

carotid arteries above the carotid bifurcation as well

5:19

as seeing examples of arterial dissection

5:24

which is defined on the images above.

5:28

So, of the 25 individuals that we studied,

5:32

as you can see 13 patients had scoliosis,

5:36

twelve had craniosynostosis,

5:38

eight had aneurysms intracranially.

5:41

And we saw dissections of the carotid artery and the

5:45

vertebral basilar artery in three of the cases.

5:48

And many of these cases obviously had the typical

5:52

tortuosity that defines the syndrome.