Interactive Transcript
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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
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on the left side well seen we only see the jugular vein
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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
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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
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have bilateral internal carotid or common carotid artery
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medial deviation into the retropharyngeal space.
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This is an important normal variation in one particular
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setting and that is when the surgeons are contemplating
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an anterior fusion of the cervical spine.
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With an anterior fusion they're coming in through the
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retropharyngeal space and prevertebral space to get
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to the anterior portion of the vertebral body.
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And the presence of the internal carotid artery in this
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medial location could be disastrous if they're not
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expecting it because they could injure either of these
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carotid arteries on their approach to do a fusion
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anterior fusion of the cervical spine.
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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,
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you might see the carotid artery medial but in the next
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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
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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
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common of the intrinsic vasculopathies of the carotid
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space is going to be fibromuscular dysplasia.
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Fibromuscular dysplasia on imaging.
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As you see in this carotid arteriogram is typified by
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areas of narrowing and widening of the vessels be it the
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carotid arteries or the vertebral arteries in the neck.
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Most commonly,
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it's going to involve the internal carotid arteries.
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However,
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it may also involve the common carotid arteries
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and as I said previously, vertebral arteries.
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You may also see it involving
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the external carotid artery.
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And this typical beaded shape
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identified by areas of narrowing followed by areas of
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widening and that little kind of quirkscrew look
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to it is typical of fibromuscular dysplasia.
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And this may lead to carotid dissections.
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And in this case,
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an example of a carotid dissection leading to a
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cavernous rotted fistula secondary to the dissection
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into the cavernous sinus fibromuscular dysplasia,
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the most common of the vasculopathies of the carotid
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artery that are primary to the carotid space.
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I mentioned previously the fact that we have a high rate
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of seeing cases of Loeys-Dietz syndrome at Johns
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Hopkins because Hal Dietz attracts these
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patients and evaluates them.
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This is a type of vasculopathy or type of connective
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tissue disorder analogous to Marfan syndrome.
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And as you can see by this article that was written
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by one of my research fellows, Vanita Rodriguez,
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along with Loeys and Dietz,
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with me being the senior author on this paper.
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The Loeys-Dietz syndrome is described as showing the
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triad of arterial tortuosity and aneurysms
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hypertelorism and bifid uvula, or palate.
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So that hypertelorism and bifid uvula and palate
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distinguishes it from Marfan syndrome which obviously
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has a lot of the manifestations of the vascular disease.
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However, has other manifestations,
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that being the lens dislocations and the elongated
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vertebral bodies and large size.
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So we looked at some of the patients who had
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Loeys-Dietz syndrome, in this case, 25,
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that had head and neck CT scans and MRI scans and what
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we found was indeed torturous blood vessels which are
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seen in this three-dimensional reconstruction
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of the CTA in this individual.
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Notice the corkscrew-like appearance of the internal
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carotid arteries above the carotid bifurcation as well
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as seeing examples of arterial dissection
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which is defined on the images above.
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So, of the 25 individuals that we studied,
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as you can see 13 patients had scoliosis,
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twelve had craniosynostosis,
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eight had aneurysms intracranially.
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And we saw dissections of the carotid artery and the
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vertebral basilar artery in three of the cases.
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And many of these cases obviously had the typical
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tortuosity that defines the syndrome.
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