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This is an MRI of the brain in a child with

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seizures and developmental delay,

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and we can see a severe paucity of sulcation.

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The brain surface is relatively featureless.

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We see a very rudimentary Sylvian fissure here

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on the right and a shallow version of a

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similar structure here on the left.

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Otherwise,

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very featureless, we see a little bit of,

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in this parasagittal aspect of the frontal lobes,

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we see the anterior aspect of the cingulate gyrus.

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If we go here to the sagittal image,

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we see the parieto-occipital fissure,

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we see the calcarine sulcus,

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but otherwise, we're seeing very few sulcations

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within the cuneus of the occipital lobe,

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as well as the lingual gyrus of the occipital lobe.

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If we go a little bit off to the side,

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we're also seeing minimal sulcation,

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very featureless brain.

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In addition to the surface findings of

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a relatively featureless brain,

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we're seeing a very thickened,

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what looks like cortex,

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but not all of this is really cortex.

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If we look at an image here,

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we can see the gray matter at the periphery,

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but all of this is actually an intervening area.

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Here in the right occipital lobe,

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we can see this is the cortex.

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These little areas where it looks slightly bright

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is actually white matter.

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It is what's called the cell sparse zone.

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Then beneath that is an additional

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band of gray matter.

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That band of gray matter follows the surface of

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the brain throughout both cerebral hemispheres.

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This deeper gray matter that's in a band like

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configuration is not in the normal location,

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so it's called heterotopic gray matter.

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This pattern of heterotopic gray matter

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is called band heterotopia.

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The smooth surface of the brain is known

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as lissencephaly.

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Lissencephaly,

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especially the more severe forms,

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is often associated with a

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band type heterotopia.

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Band heterotopia is an abnormality of neuronal migration.

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We can see other abnormalities here,

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that there's a severe loss of the cerebral

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white matter volume.

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Overall,

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the brain doesn't have a lot of the

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landmarks we're used to seeing.

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The lateral ventricles have a slightly

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dysmorphic appearance due to the abnormal

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configuration of the surrounding white matter.

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And we can see the cerebellum looks closer

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to normal than the cerebral hemispheres.

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The cerebellar volume is a little

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bit lower than usually seen,

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but compared to the cerebral hemispheres,

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they're relatively preserved.

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And this is an abnormality known as

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lissencephaly with bandtype heterotopia.