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This is an MRI of the brain in a six

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year-old child with neurofibromatosis

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type 1, and we can see there's

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thickening of the prechiasmatic

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segment of the optic nerves bilaterally.

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I'm going to zoom in.

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Thickening of the prechiasmatic segment

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of the optic nerves bilaterally, also

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of the canalicular segment going through

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the optic canal, and the posterior

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orbital segment of the optic nerves.

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And we can see it goes in and out of a

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plane right here, related to tortuosity.

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On this coronal image, we can see

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thickening of the prechiasmatic

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segment of the optic nerve.

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Canalicular, and the posterior

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orbital segments of the optic nerves.

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This is bilateral fusiform optic nerve

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gliomas extending to the chiasm without

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significant involvement in the optic tracts.

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Now there is involvement of the hypothalamus,

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So this here is indistinctness of

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the hypothalami and it's important to

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remember the hypothalamus and the optic

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chiasm are in contact with one another.

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So people sometimes will refer to

1:05

this involvement as a hypothalamic

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slash chiasmatic glioma.

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So this patient has bilateral fusiform

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optic nerve gliomas with additional

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hypothalamic chiasmatic component.

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Now that's not the whole

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story in this patient.

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If we look at flow voids, here is the

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left middle cerebral artery flow void.

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We're not seeing a corresponding flow

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void for the right middle cerebral artery.

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Now we are seeing these little speckled

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areas of flow voids surrounding

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the region of the carotid terminus.

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Again, on this coronal image, we see the

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left middle cerebral artery flow void.

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We're not seeing a discrete paired

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of similar caliber flow void for

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the right middle cerebral artery.

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MR angiogram was performed and we can

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see We're not seeing the M1 segment of

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the left middle cerebral artery, clearly.

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This is the M1 segment right here.

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This is the normal caliber

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of the left M1 segment.

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We're not seeing a normal

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caliber of a right M1 segment.

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We are seeing these small

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little vessels surrounding the

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region of the carotid terminus.

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Here is the MR angiogram.

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We see the left middle cerebral artery.

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We do not see a right middle cerebral artery.

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Arterial spin labeling perfusion shows

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asymmetrically decreased perfusion

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in the right middle cerebral artery

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territory, as well as the right

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anterior cerebral artery territory.

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We're seeing a normal perfusion pattern in

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the left anterior cerebral artery territory,

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the left middle cerebral artery territory, and

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the left posterior cerebral artery territory.

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Catheter angiography confirms that

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there's a normal A1 segment of the

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right anterior cerebral artery, but

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we're not seeing a normal M1 segment

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of the right middle cerebral artery.

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We are seeing these little vessels.

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It's a serpentine collateral

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surrounding the carotid terminus.

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This hazy or ethereal appearance has been

3:12

referred to as moyamoya vasculopathy.

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Moyamoya is a Japanese term

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meaning hazy or ethereal.

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It does not mean puff of smoke.

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That's a mistranslation from the

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original article when it was proposed.

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It means hazy or ethereal.

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So Thank you.

3:28

That's because especially prior to high

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resolution imaging, you couldn't see

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each of these individual little vessels

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so it looked like a hazy little blush.

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Here is a right external carotid artery

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injection, where we see the right

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middle meningeal artery as well as the

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superficial temporal artery, but we're

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not seeing any intracranial extension.

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This is dynamic MR angiography,

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again confirming the absence of a

3:56

significant caliber of the M1 segment

3:58

of the right middle cerebral artery.

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And we're seeing no significant asymmetry

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in the external carotid arteries.

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a pial synangiosis revascularization.

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We can see some, here we see artifact from

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a prior surgical procedure that involves

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taking the superficial temporal artery and

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a muscle pedicle and sewing it to the pier.

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This does not provide immediate

4:29

revascularization, so it's

4:31

not used for an acute stroke.

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But over time, that results

4:35

in collateral formation.

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So we see on this follow-up MR angiogram,

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we see hypertrophied superficial temporal

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artery, which now goes intracranial

4:49

and has branches that now connect and

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revascularize the middle cerebral artery.

4:55

So the postoperative angiogram of

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the external carotid artery injection

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shows a hypertrophied superficial

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temporal artery with extension to

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branches of the middle cerebral artery.

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We see a parenchymal blush, and we see

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intracranial venous structures cortical

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veins and superior sagittal sinus.

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So this is successful pial synangiosis

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of a right-sided Moyamoya vasculopathy.

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So it's important to be aware of the

5:30

relationship of neurofibromatosis

5:33

type 1 with moyamoya vasculopathy.