0:00

I wanna review a few normal variants,

0:02

and this has helped me, uh, quite a bit, uh, over the years.

0:07

So there is a normal structure called a ate cyst,

0:10

which is just a remnant structure.

0:12

People will also call it a coarctation

0:14

of the lateral ventricle that occurs at the area

0:17

of the white circle.

0:18

So it's right at the tip

0:19

of the frontal horn lateral ventricle.

0:22

If you have a cystic structure at this location,

0:25

you can be confident it is a normal variant prenatal cyst.

0:29

On the other hand, if you have a cystic structure either

0:31

above it or below it, that is not normal.

0:34

And almost always those are gonna be

0:36

abnormalities related to prematurity.

0:38

So the blue circle, if you see a cystic structure in this

0:41

location, you should be worried about cystic

0:43

periventricular leukomalacia.

0:46

If you see a cystic structure at the red circle,

0:48

that is almost always gonna be a subependymal cyst from

0:51

prior germinal matrix hemorrhage.

0:53

So just keep that in mind as you're looking at cystic,

0:56

abnormal or normal cystic structures in the brain.

0:59

Just a reminder, the grading system

1:02

for germinal matrix hemorrhage is based on

1:05

cts from 1978 was when pap pill first described the germinal

1:09

matrix hemorrhage grading system.

1:11

So of course we have infants

1:12

who were much more premature surviving much longer

1:16

in this day and age.

1:17

Um, so we will see hemorrhage not only involving the

1:21

posterior germinal matrix,

1:22

but uh, we'll be able to see much,

1:24

much greater detail than they could at CT back in 1978.

1:29

And I always tell my residents,

1:30

and I learned this from one of my favorite, um,

1:32

attendings when I was a resident, is that rule number one

1:35

for any head ultrasound is to be where any areas

1:38

that are brighter than the choroid plexus.

1:41

So the choroid plexus is your internal control for

1:44

how bright a structure is allowed to be

1:46

and still be considered normal at a head ultrasound.

1:49

So we're gonna go over a few of these.

1:51

Um, anatomic variants.

1:53

We already discussed prenatal cyst,

1:55

but it is this, uh, kind of teardrop shape,

1:57

cystic structure at the apex

1:59

of the frontal horn lateral ventricle.

2:01

It's also called a pseudo cyst

2:03

or a lateral ventricle cooptation.

2:05

People also call it a frontal horn cyst.

2:07

Anytime there's multiple names for the same structure,

2:10

I always forget all of the names,

2:12

but just remember cyst is what most people call it.

2:15

It is a normal structure. It goes away over time.

2:18

Here is your MRI comparison

2:20

where you can see these teardrop shapes T two signal foci at

2:24

the kind of right at the apex

2:26

of the frontal horn lateral ventricles.

2:29

Another normal variant I want

2:31

to highlight is something called a septal vein.

2:33

So these are transient structures that, um, in utero are,

2:37

are patent vessels, but they involute over time.

2:41

Um, they are these thin linear structures that go

2:44

through the Cajun septum pullum.

2:45

They are totally normal structures.

2:47

I have seen, um, these erroneously called

2:50

syne from prior infection, prior ventriculitis,

2:53

and these are just totally normal structures

2:55

that just like a al cyst will involute over time.

2:59

So these are called septal veins.

3:02

Uh, this patient was super helpful for education purposes

3:06

because this patient not only had septal veins,

3:08

so these again, thin linear epigenic structures in the

3:11

cavem septum bluestem.

3:12

But this patient also had ventricular stripe vasculopathy.

3:15

So these are these branching genic sort

3:18

of chicken feet looking structures in the deep grain nuclei.

3:21

And let's see if my syne will actually play. Yay.

3:24

So this patient has not only, uh,

3:26

a lenticular right vasculopathy,

3:28

those branching genic foci in the deep grape nuclei,

3:32

but this patient also had septal veins.

3:34

So two different normal variants.

3:37

You will hear some sort of controversy if you will,

3:41

over whether mineralizing vasculopathy

3:44

also called lul, right?

3:45

Vasculopathy means anything,

3:47

but it is a super non-specific finding.

3:49

It's associated with lots of different abnormalities, um,

3:53

but also is seen in normal patients.

3:56

So unless there's something else

3:57

that I see abnormal on a head ultrasound,

4:00

I will describe meticulous right vasculopathy

4:03

as a normal finding and then move on.

4:05

I don't even put it in the impression typically

4:08

'cause at our institution, our NICU colleagues don't screen

4:10

for torch infections.

4:12

Um, when we see mineralizing vasculopathy, another variant

4:16

that I wanted to highlight is a choroid plexus cyst.

4:19

So that is this cystic structure in the choroid plexus, uh,

4:23

indicated by this white arrow.

4:25

Unless they are larger than one centimeter,

4:28

these are completely normal variants.

4:31

When they're larger than one centimeter in diameter, they,

4:33

there is some association with um, aneuploidies

4:36

and then the patient needs to undergo

4:37

additional clinical screening.

4:39

If we see just tiny choroid plexus cysts,

4:42

we describe them in the findings

4:43

and then I don't even put them in

4:45

the impression of my report.

4:47

There's another example

4:48

of an even tinier choroid plexus cyst, um, on

4:51

that right side indicated by that white arrow.

4:54

For me, sometimes I will be a little, it,

4:56

it can be confusing if it's, um, old blood,

5:00

old germinal matrix hemorrhage

5:01

or old choroid plexus uh, hemorrhage

5:03

and it's kind of going undergoing cystic evolution

5:05

that we expect of hemorrhage.

5:07

Um, but that's where follow-up will be super helpful.

5:09

So a quad plexus cyst might become less conspicuous over

5:12

time as the baby gets older, but

5:14

otherwise it should be unchanged.

5:16

Whereas hemorrhage should change in appearance over time,

5:19

it will undergo some sort of evolution

5:21

and eventually disappear.