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This is an axial T2-weighted image

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in an 8-year-old child

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with neurofibromatosis type 2

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2 performed for routine

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outpatient surveillance.

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There's no symptoms at the time.

0:09

This is just to evaluate the current state

0:12

of the disease in that patient.

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We do not see any areas of

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myelin vacuolization in the globus pallidus

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or in the thalami.

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We're not seeing any definite abnormalities

0:25

in the brainstem.

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Now, we do see an area of hyperintense signal or

0:31

myelin vacuolization at the interface of the

0:33

right middle cerebellar peduncle and the

0:35

right cerebellar deep white matter.

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We see this here on this coronal STIR image.

0:42

Five years later, that is no longer present.

0:46

So, this is just an example of

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how this patient,

0:52

with the area of myelin vacuolization,

0:54

they can disappear.

0:56

That is another reason why

0:58

these are appropriately

1:00

described as myelin vacuolization.

1:01

They are not hamartomas because hamartomas

1:04

would not disappear.

1:06

So, what else do we see in this patient?

1:09

It's subtle,

1:12

but if we look at the marrow here,

1:14

this T2 hyperintense area here is marrow,

1:18

in the right sphenoid wing,

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and here on the left,

1:24

is asymmetrically smaller.

1:31

If we look at the CT scan that was

1:33

performed for other reasons,

1:35

we can see there is asymmetrically decreased

1:38

caliber of the left greater sphenoid wing.

1:41

This is a sign of left sphenoid wing dysplasia.

1:45

It's on the milder side,

1:48

but sphenoid wing dysplasia is one of the

1:51

known associations in neurofibromatosis type 1.

1:55

Why is this important to recognize?

1:58

Well,

1:59

in this patient who actually intracranially

2:03

doesn't have a significant burden of myelin

2:06

vacuolization or other characteristic

2:08

findings of NF1,

2:10

this sphenoid dysplasia can be especially

2:13

relevant if the patient does not have a

2:15

confirmed diagnosis of

2:17

neurofibromatosis type 1,

2:19

because that is a potential diagnostic

2:23

criteria, sphenoid dysplasia.

2:25

So that is important to recognize,

2:28

even though it is subtle in this MRI,

2:31

it can be helpful.

2:32

Additionally, depending upon the severity

2:35

of sphenoid dysplasia,

2:36

that can result in abnormalities of

2:39

eye movement and eye positioning,

2:42

which can result in double vision

2:43

and other abnormalities,

2:45

that's important for the ophthalmologist to

2:47

be able to know and be aware of.

2:50

Now, this milder sphenoid dysplasia,

2:52

this mild asymmetry, may not have any

2:55

clinical manifestation, but again,

2:57

it may be

2:59

enough evidence to give the patient another

3:03

diagnostic criteria that could confirm

3:05

the diagnosis of neurofibromatosis type 1

3:08

in some patients.