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This is an MRI of the brain

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in a five-year-old child

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with neurofibromatosis type 1.

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We can see areas of myelin vacuolization

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in the globus pallidus bilaterally,

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right greater than left.

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The right's minimally expansile.

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We can see some abnormality

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in the deep cerebellar, gray and white matter.

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Additionally, areas of myelin vacuolization.

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The brain parenchyma,

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otherwise, looks normal.

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So, these are all classic findings

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of neurofibromatosis type 1.

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In this patient, however,

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we can see some tortuosity of the

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optic nerves bilaterally,

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which it's always hard to know

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what amount of tortuosity do you get worried about?

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Well, in neurofibromatosis type 1,

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given their propensity for optic pathway gliomas

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and given that tortuosity

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is one of the first manifestations of

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an optic pathway glioma,

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we always have to be very careful to scrutinize.

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And on this coronal T2-weighted image,

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we can see here,

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this dark circle here is the optic nerve,

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the thin rim of hyperintense signal

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around it is CSF within the optic nerve sheath.

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As I go posteriorly,

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the right optic nerve in the posterior

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orbital segment is subtly,

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is subtly bigger and more hyperintense on

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T2-weighted image than the left.

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While it's subtle, we see it.

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Do we see a corresponding abnormality on

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the axial image?

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That's hard to say.

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But if we look at the post-contrast image,

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we see subtle focal enhancement

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right here in the right optic nerve,

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exactly in the place where we're seeing subtle

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enlargement and subtle hyperintense signal.

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So, again,

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I don't want to use the word subtle too much,

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but objectively speaking,

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the right optic nerve is a little bit bigger

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than the left.

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Objectively speaking,

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it's more hyperintense than the left,

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and objectively speaking, it is enhancing.

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So while at first I was saying,

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well, it's subtle,

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given the corroboration of

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these different findings,

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this is not a possible optic pathway glioma.

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This is an optic pathway glioma.

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Now, given the setting of neurofibromatosis type 1,

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where this is not an unexpected finding,

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it is not something that will get any surgery

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because it cannot be resected

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without compromising vision,

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it cannot be treated with radiation therapy

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without potentially having complications.

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So, that's only performed if there's

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progression of a lesion.

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This will be followed with detailed

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ophthalmologic examinations

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and imaging surveillance.

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The imaging surveillance,

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we need to make sure that whatever imaging

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protocol we were able to see these findings,

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we can employ that on the follow-up study,

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or even higher resolution,

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because we want to be able to see,

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is this progressing? Is this expanding?

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Is this getting bigger on

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a cross-sectional basis?

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Is this longitudinally extending anterior to

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the globe or posteriorly to the chiasm?

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So, those are the types of things.

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Once you find a glioma,

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when you're following it up,

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you want to be able to provide that information.