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This is a T2-weighted MRI image of the brain

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in an eight-month-old child with a family

0:07

history of tuberous sclerosis complex.

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So, this patient has not yet had seizures,

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does not yet have clinical manifestations

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of tuberous sclerosis complex,

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and this is being done as a part

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of a genetic evaluation.

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So, as we look on T2-weighted imaging,

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we're not seeing anything stand out.

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Now we're seeing the white matter

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is normally hyperintense,

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that is related to the water content

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of the ongoing myelination,

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until, once this is fully myelinated,

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this becomes more hypointense.

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But now we still see some bright signal.

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T1-weighted imaging.

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We're seeing some bright signal from

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the protolipids of myelin,

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and then FLAIR imaging,

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which, again,

0:57

shows some hyperintense signal

0:59

in the white matter.

1:00

FLAIR is not usually the most helpful for

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evaluating brain parenchyma in the

1:06

first year or two of life.

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We actually use it mostly to evaluate

1:11

the extra-axial space,

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like to look for subdural collections and such,

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but it's not usually the most effective,

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given the ongoing myelination in a newborn.

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T1-weighted imaging is a great way to look

1:24

for areas of dysplasia in tuberous sclerosis

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complex. In maturely myelinated individuals,

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FLAIR and T2-weighted imaging are good,

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and a lot of times,

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with that intermediate myelination,

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T2-weighted imaging can be more helpful than

1:37

FLAIR. But here, we're not seeing anything.

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But if you look closely,

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we do see a little suggestion of a bump along

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the lateral margin of the posterior body

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of the right lateral ventricle

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susceptibility.

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Weighted imaging shows no mineralized

1:53

subependymal nodules. But this one here,

1:55

given the family history of

1:56

tuberous sclerosis complex,

1:58

is a hint that maybe this patient does

2:01

have tuberous sclerosis complex,

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but we just can't definitely tell it.

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But what's a way to look for areas of dysplasia?

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Well, one of the ways he can do is wait.

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We've already said that. T1-weighted imaging.

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There's enough myelin proteolipids that we can't

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see the hyperintense signal very well.

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T2 and FLAIR imaging.

2:21

There's sort of this heterogeneous myelination

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pattern that no longer is as obvious

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at this stage of intermediate myelination.

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Well,

2:32

there's one more technique that we can use.

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It's a technique that's not as commonly used

2:38

today with all these modern imaging

2:40

sequences that we have.

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This is Mr. With magnetization transfer.

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It's a T1-weighted sequence,

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and it accentuates these areas of dysplasia.

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So this individual,

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where all we saw was a hint of a.

2:54

Maybe a subependymal nodule.

2:56

We're seeing dysplasia here, here, here, here.

2:59

Here.

3:04

So there's multifocal areas of cortical

3:06

dysplasia throughout both cerebral hemispheres.

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Left occipital lobe.

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This would have been missed on T1-weighted

3:12

imaging. T2-weighted imaging.

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FLAIR imaging. Now,

3:15

the only hint we got that this patient had tuber

3:18

sclerosis on conventional imaging was this

3:21

little subependymal nodule here. But in reality,

3:24

body, they had multiple manifestations.

3:29

Well, if we fast forward several years,

3:32

this is a FLAIR image.

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We can see these T1 with magnetization

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transfer areas of hyperintense signal

3:40

correspond to what we saw,

3:42

what we eventually see on this FLAIR image.

3:47

See this area of dysplasia here?

3:49

An area posterior to it,

3:54

this area here. So, again,

3:58

we can see this area here in the

4:00

left inferior frontal gyrus.

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So these multifocal areas of dysplasia which are

4:06

very clearly identified on FLAIR imaging in the

4:10

background of a normally myelinated brain,

4:14

were almost impossible to identify in T1

4:17

weighted imaging at eight months of age,

4:19

almost impossible to identify

4:21

in T2-weighted imaging,

4:22

almost impossible to identify in FLAIR imaging.

4:25

However,

4:25

are highly conspicuous on T1-weighted

4:28

imaging with magnetization transfer.

4:30

So this individual who was undergoing genetic

4:34

testing was able to be identified as, yes,

4:38

having a brain imaging phenotype that goes with

4:41

the clinical suspicion of the genetic history

4:44

suspicion of tuberous sclerosis complex.

4:46

They were able to get an EEG,

4:48

able to get early follow up with a neurologist,

4:51

and that was very helpful.

4:54

So this shows that

4:57

understanding the proper imaging sequences to

4:59

evaluate tuberous sclerosis complex at

5:02

given ages is very important.

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One more thing I will add.

5:07

At a young age,

5:08

we did not see any mineralized subependymal

5:11

nodules on susceptibility-weighted imaging.

5:16

As they grew older,

5:17

we could see mineralized subependymal nodules

5:19

along the lateral margin of the anterior

5:21

body of the lateral ventricles,

5:22

as well as more posteriorly.

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So that shows that the mineralization and the

5:27

subependymal nodules change over time.

5:30

So that's something to follow.

5:31

But the key point in this case is to show the

5:34

benefit of T1 with magnetization transfer,

5:38

especially in evaluating areas of dysplasia in a

5:41

background of an incompletely myelinated brain.