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This is an MRI of the brain

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in a nine-and a half year old child with headaches.

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And at first glance, everything looks normal.

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In a normal MRI,

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I look for the size and symmetry

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of the lateral ventricles.

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The lateral ventricles look normal size and

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appropriate morphology and symmetry.

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Third ventricle.

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Fourth ventricle.

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At this age,

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we're seeing near complete to complete myelination,

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where on T2-weighted imaging,

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everything looks hypointense

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for the myelinated white matter.

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By nine half years old,

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only white matter, which is unmyelinated,

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is very subtle peripheral juxtocortical

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connections in the frontal lobes,

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which is typically below the ability

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to detect on MR imaging.

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So, everything looks fairly normal.

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It's important,

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when looking at MRI,

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to look at all imaging sequences,

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one of which is the diffusion weighted image.

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And people are used to using diffusion

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weighted imaging to look for strokes,

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and diffusion weighted imaging is excellent

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for looking at strokes,

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excellent for looking for abscess, empyema,

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things like that.

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But there's more information provided.

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We can already see in here,

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there's a different appearance between the gray matter at

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the periphery and the white matter.

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The gray matter looks a little bit brighter,

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and that's normal.

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That's expected.

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Well, we can use that to our favor.

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As we're looking through here,

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we see a little focus of gray matter right here

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along the superlateral margin of the

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body of the left lateral ventricle.

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If I look at this T2-weighted image,

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I see a very subtle nodular area of gray matter.

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If I go back to this sagittal T1-weighted image,

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I can see a small focus of gray matter.

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And on the coronal STIR,

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here is the right caudate body.

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Here's the left caudate body.

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Just superior to that is a small

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focus of gray matter.

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So while it otherwise looks like a normal study,

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the diffusion weighted image,

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which normally we don't think about using

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for things other than stroke or abscess,

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actually was able to alert us to a very small

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focus of gray matter heterotopia.