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This is an MRI performed of

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a woman who is pregnant.

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And so,

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the MRI is focused on the fetus itself,

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in particular, the brain.

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There was questions on the ultrasound about the

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size of the brain and the features of the brain.

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And so, this MRI was performed.

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And we can see here posteriorly,

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we can see some sulcation.

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It's difficult to see in fine detail in

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a fetal MRI because of the small size,

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but you can see there's some sulcation

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and some different substructures.

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But if we go to the frontal lobes,

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in particular the frontal poles,

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this is very featureless.

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Same with on the left side,

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so both sides we're not seeing much.

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If we go to the sagittal view,

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we're seeing a very featureless frontal lobe.

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Overall,

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the brain size is smaller than expected.

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If you look at the craniofacial ratio,

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the head does not,

0:57

and the brain does not project up significantly

1:00

relative to the size of the face.

1:02

Here is the nasal bone,

1:03

down to the lower lips and the chin.

1:05

So we have a smaller than expected brain

1:08

with a paucity of sulcation anteriorly.

1:12

The lack of sulcation prior to a term infancy is

1:18

very challenging to assess normal from abnormal.

1:21

But this infant is, I believe,

1:23

nearly 30 weeks gestation,

1:25

at which time you should have more sulcation

1:28

than this anteriorly.

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Also, there shouldn't be such an asymmetry

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between the frontal lobes,

1:34

where we're seeing very little sulcation,

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and posteriorly, where we're seeing much more.

1:39

And this right here is highly suggestive of an

1:43

anterior predominant lissencephaly spectrum disorder.

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This was confirmed on postnatal imaging,

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and it is noted that an anterior predominant

1:55

lissencephaly oftentimes is related

1:58

to an abnormality in the DCX gene.

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DCX.

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That's in contrast to the posterior

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predominant lissencephaly,

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which is related to abnormalities

2:08

of the LIS1 gene.

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So this is something that can be done where,

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on the imaging,

2:13

you can at least give some hints at what genetic

2:18

defects might be causing with the structural findings,

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which can help guide the geneticists,

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the maternal fetal medicine doctors,

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the neonatologists and neurologists

2:30

on what genetic tests to order,

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because there are so many possible

2:33

genes out there.

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But for lissencephaly or relatively

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featureless parts of the brain,

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anterior predominant lissencephaly,

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you think DCX gene.

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Posterior predominant lissencephaly,

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you think the LIS1 gene.