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This is an MRI scan of the brain

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in a five year-old child

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with developmental delay.

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One of the first things we see is

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there's an abnormal configuration of

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the lateral ventricles.

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The body of the lateral ventricles

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are somewhat parallel,

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whereas normally,

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they sort of angle laterally as you go posteriorly.

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So, there's a parallel body of both lateral ventricles.

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As we go inferiorly,

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the atria and occipital horns of both lateral

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ventricles are larger than we typically see.

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This is called colpocephaly.

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As we go up,

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we're seeing no intervening corpus callosum.

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If we go to the sagittal T1-weighted image

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for the midline structures,

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we do not see any aspect of the corpus callosum.

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Additionally,

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normally just above the corpus callosum

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is the cingulate gyrus,

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which runs anterior and posteriorly.

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Here we do not see that.

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We see these radiating gyri that come all

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the way down to the third ventricle here.

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We also see here's the anterior commissure,

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which is a little on the small side,

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but otherwise,

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we're not seeing any commissural

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fibers of the corpus callosum.

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If we look on a coronal image,

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we can see a vertically oriented third ventricle

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and there's no intervening corpus callosum.

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

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the distal branches of the anterior cerebral

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artery have a very low position.

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Normally, they would go superior to the corpus

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callosum and extend as the pericallosal artery.

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Those have a very low position

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that we can see right here,

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nearly as low as the level of the internal

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cerebral veins.

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One of the other things we see,

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in addition to this vertically

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oriented third ventricle,

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there's a characteristic configuration of the

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interface between the third ventricle

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and the lateral ventricles,

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which has sometimes been referred to

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as a Texas longhorn sign,

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or in some cases like this,

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may look sort of like Bullwinkle, the moose.

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Along the medial margin of the body

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of those lateral ventricles,

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there's a bundle of white matter here.

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These are the fibers that would have crossed

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the corpus callosum, but they don't.

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So, they are directed anterior posteriorly

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instead of directed laterally

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to go across the corpus callosum.

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This area is known as Probst bundles.

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One other thing we see in this child

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is there's an increased axial length of both globes.

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If we look from the anterior aspect of the

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cornea to the level of the

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optic nerve insertion,

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there's sort of some posterior protrusion

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and an increased axial length.

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This needs to be further characterized with an

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ophthalmologic examination and may be indicative

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of some underlying genetic underpinnings

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to this disease process.