0:01

When we have a child presenting with acute neurologic

0:04

deficit where a stroke is considered, we might

0:08

start out with an MRI study rather than a CT study.

0:15

Again, remember that the CT, CTA, and CT

0:18

perfusion is multiple scans of the same anatomy

0:24

again and again as part of that CT perfusion,

0:27

and therefore, it is a higher radiation

0:30

dose than a simple CT scan without contrast.

0:34

So therefore, in the children who are

0:36

suspected of having a stroke, we might start

0:39

with an MRI scan because of the absence

0:42

of any radiation exposure to that patient.

0:46

This was just such a patient—

0:48

a child who presented with

0:50

aphasia.

0:52

So, children presenting with possible stroke,

0:55

we have a different differential diagnosis,

0:58

obviously, than an adult where we're

1:01

most likely considering atherosclerosis.

1:04

So let's look at this patient.

1:06

Here is the diffusion-weighted scan.

1:08

Again,

1:08

the first thing I'm going to go to is

1:10

the DWI to determine whether there's a stroke.

1:13

Time is brain, so I go to the DWI, and on this DWI,

1:17

pretty clearly, you see that there is a relatively

1:20

large area of infarction within the left middle

1:25

cerebral artery distribution that is affecting not

1:27

only the caudate nucleus and the putamen, probably

1:31

a portion of the globus pallidus, as well as the

1:34

frontal opercular region and perisylvian region.

1:37

You also see that there are other areas

1:40

of left frontal lobe infarction.

1:43

So I've gotten infarction.

1:44

I'm on the phone calling the clinician as I

1:48

continue to look at the additional whole sequences.

1:51

So the next thing to do is we're gonna look

1:54

for our gradient echo or susceptibility-

1:56

weighted scan to see whether there's any

1:58

hemorrhage in this area of infarction.

2:03

And we do not see blood

2:04

products, so that's a good thing.

2:06

So the patient is potentially a candidate for

2:09

a thrombectomy if that is indeed present.

2:12

And next, we would go on to the MRA.

2:17

I just wanna make a comment about the value of FLAIR

2:21

imaging and diffusion-weighted scanning together.

2:26

So what we have

2:28

found in neuroradiology is that a patient

2:32

who has a diffusion deficit on the DWI, where

2:37

the FLAIR scan is still normal, usually means

2:42

that the infarct is less than six hours old.

2:45

However, if we see the abnormality on DWI

2:49

and bright on the FLAIR scan, which you see

2:53

here, it's usually greater than six hours old.

2:56

That's useful because the sooner we get to do

2:59

thrombolysis or thrombectomy, the better the prognosis.

3:03

In some cases, something that we

3:05

would call a "wake-up stroke."

3:07

The patient wakes up from sleep with a neurologic deficit.

3:11

We don't know how old the neurologic deficit is.

3:15

The DWI-FLAIR combination would be able to separate

3:18

it into those that are six hours or younger.

3:22

Versus those that are older than six

3:24

hours on a wake-up stroke, where you don't

3:26

know when the patient was last normal.

3:29

So in this child, we're saying, all right,

3:31

well, this stroke is greater than six hours old.

3:33

It's still possibly one that we would intervene on.

3:37

So we would want to go to the

3:39

MRA in the MR perfusion study.

3:41

Here is the MRA study, and I'm going to get to the tumble

3:48

view, which is my favorite view, where we're seeing.

3:51

The vessel look head over heels.

3:53

And what we see on this head-over-heels view is

3:58

that the M1 segment of the middle cerebral artery

4:01

on this patient is showing areas of narrowing and

4:05

expansion and narrowing and expansion across the M1

4:09

segment compared to the contralateral right side.

4:14

So this is an abnormal segment of

4:16

the blood vessel, and we do not see.

4:20

Thrombosis; what we see is vasculopathy.

4:25

So the differential diagnosis for vasculopathy in a

4:29

teenager, a 12-year-old, 13-year-old, as in this

4:33

case, is relatively wide, is my portion of geography.

4:40

One of the more common etiologies

4:42

would be sickle cell disease.

4:43

Where you may have a vasculopathy on that basis and

4:47

or thrombosis on that basis in a different age group.

4:51

We might also consider IV drug abuse with

4:55

a vasculopathy or vasculitis on that basis.

4:59

Secondary to illicit drug use or cocaine use, for

5:03

example, could cause a vasculitis or vasculopathy.

5:07

There are some other entities,

5:09

collagen vascular diseases such as.

5:13

You know, your sarcoid or lupus or other

5:17

rheumatoid etiologies where you might have a

5:19

vasculopathy in a child, a juvenile rheumatoid

5:23

arthritis patient, for example, HIV is another.

5:27

There are a lot of infectious etiologies that

5:30

are different than atherosclerotic disease, which

5:33

is what we would normally suspect in an adult.

5:39

So this patient did have, uh, perfusion imaging

5:42

and it showed a matched defect to the DWI sequence.

5:49

These are not in color, but they show that there was

5:53

the same area of involvement as the DWI and therefore

5:58

there was not salvageable tissue in this individual.