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This is an MRI of the brain

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in an eight-year-old child with headaches,

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with also a known history of neurofibromatosis Type 1.

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So, at first glance, we look at this,

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we see everything is symmetric

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on this axial T2-weighted image.

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Now, if we look at this axial FLAIR image,

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we see some hyperintense signal in the region

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of the pulvinar of the thalamus bilaterally.

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But otherwise,

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we're not seeing a lot of supratentorial

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signal abnormalities.

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That can be common because

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every patient with neurofibromatosis Type 1

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has a brain manifestation that

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looks a little bit different.

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Now,

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I want to make sure we discuss these areas of

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bright signal have sometimes, in the past,

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been referred to as UBO's

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or Unidentified Bright Objects,

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or hamartomas.

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Well, they're not hamartomas.

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We now know that they're actually

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areas of myelin vacuolization.

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We know this because they may appear

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as a child is growing,

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and they may disappear during adolescence

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and young adulthood.

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Hamartomas don't disappear.

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And since we know what they are,

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myelin vacuolization,

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they're not really unidentified bright objects.

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They're areas of myelin vacuolization

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in neurofibromatosis Type 1.

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If I scroll to the brainstem,

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we can actually see here

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in the right aspect of the pons,

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we see an area of signal abnormality.

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I'm going to zoom in and we can see this patchy

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area of T2 hyperintense signal.

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We can see an additional area

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of T2 hyperintense signal

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in the lateral aspect

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of the right middle cerebellar peduncle.

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And we can also see some bright signal in the

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deep cerebellar gray matter in the right

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cerebellar hemisphere,

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in the region of the dentate nucleus.

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These are all areas of myelin vacuolization

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in the setting of neurofibromatosis Type 1.

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If we look closely at the sagittal image

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and we identify the basion to the opisthion,

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if we draw a line connecting them,

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that line approximates the plane

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of the foramen magnum.

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The cerebellar tonsils extend 13 mm below

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the plane of the foramen magnum.

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So, while this patient has neurofibromatosis type 1,

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this patient also has a Chiari Type 1 malformation.

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So, remember,

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a patient that has one entity can have more

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than one disease process going on,

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more than one condition.

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So, this patient has neurofibromatosis type 1

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with a relatively mild pattern

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of myelin vacuolization,

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also with a Chiari Type 1 malformation.