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This is an MRI of the brain

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in an eight-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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We can see some myelin vacuolization

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in the cerebellum,

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deep cerebellar white matter and gray matter

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in the region of the dentate nuclei.

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We've seen asymmetry in the size of the globes.

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So if we look at the orbits,

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we see tortuosity of the optic nerves bilaterally,

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which we know in the setting of

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nerve fibromatosis type 1,

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we need to be aware that tortuosity could be

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one of the early signs of an optic pathway glioma.

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But separate from the nerves,

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the globes themselves look different.

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Now, if we look at globe anatomy,

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there's the anterior chamber and the vitreous.

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If we draw a line from the anterior aspect of

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the cornea to the posterior aspect of the

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globe where the optic nerve inserts,

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this is 22 mm.

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This is referred to as the axial length.

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The axial length between globes should be similar.

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Well, the right eye is 3 mm larger

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or more than 10% larger than the left,

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but that's not the only difference

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that we see between the globes.

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If we measure the depth of the anterior chamber,

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we get slightly under 3 mm on the left.

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We measure the depth of the anterior chamber

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on the right, we get more than 4 mm.

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when an ophthalmologist makes their detailed

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measurements with special instruments

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in their office,

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but there's definitely an asymmetry.

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Additionally, the width of the cornea,

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the right cornea is 16 mm wide,

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the left is 12 mm wide.

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So, we have an enlarged anterior chamber

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both in terms of depth and width,

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and we have an enlarged eye.

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Now, increased depth of the anterior chamber

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can be a sign of glaucoma,

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and this patient ended up having glaucoma.

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The increased width of the cornea and

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increased size of the globe can be chronic

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manifestations of glaucoma.

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So, these are findings in the orbit

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in neurofibromatosis type 1,

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separate from optic pathway gliomas,

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to be aware of.

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One additional thing to notice in this patient

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is this multilobulated area

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of T2 hyperintense signal in the subcutaneous

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soft tissues of the scalp, slightly to the left of midline.

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This is a supraorbital region of the scalp.

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These areas here are hyperintense

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in T2-weighted imaging.

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Very circumscribed, discrete, marginated,

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and that results in focal thickening

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of the soft tissues here.

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And this represents a plexiform

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neurofibroma of the scalp.