0:00

Okay. This is a case of a patient,

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16 month old,

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who had a severe anoxic injury that

0:08

resulted in brain death.

0:11

First, I'm going to show you the non-contrast CTs.

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These are the non contrast CT images.

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And you can see that there's diffuse

0:17

loss of gray white differentiation.

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There's no gray white differentiation.

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You can't really make out

0:23

normal structures here,

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and that is throughout the entire brain.

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And you can see that there is some mass effect.

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There's effacement of sulci.

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You can see the lateral ventricles,

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but the third ventricle is completely effaced.

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You can't really see the basal cisterns.

0:43

Well, as we go down a little bit,

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you can see that there's some

0:48

tonsillar herniation.

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You can see that also on the sagittal CT.

0:54

Some of the venous structures look dense here,

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and that is called the pseudosubarachnoid

1:02

hemorrhage sign.

1:04

And that's because the brain is so hypodense

1:06

that the vessels sometimes look

1:10

hyperdense in comparison.

1:12

So, that's the CT.

1:15

Now, the patient also had coma,

1:18

no brain stem reflexes,

1:21

and inability to breathe on his own.

1:23

So, those are the three clinical factors that

1:26

define brain death.

1:28

So, let me show you some MR images.

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So, here's a T2 weighted MR.

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And we have the classic findings of

1:38

kind of a super scan,

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where you've got severe swelling

1:42

and hyperintensity of the cortex

1:46

and of the deep brain nuclei.

1:49

And you can see,

1:50

again, there's effacement of sulcia.

1:53

There's some swelling with low lying tonsils.

1:56

We can take a look at the diffusion

1:59

weighted images.

2:00

So, these are the diffusion-weighted images

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that show DWI hyperintensity consistent with

2:07

restricted diffusion throughout the cortex.

2:10

The cortex, again, is swollen.

2:13

The deep gray nuclei are all involved.

2:16

There's some involvement of the brain stem.

2:20

There's some involvement of the white matter.

2:23

So, these findings are what you see with severe

2:27

anoxia, but it's not specific for brain death.

2:32

Some patients with findings that look like this

2:35

can partially recover.

2:36

Let me show you

2:37

the sagittal T2 weighted images.

2:39

You can see there's some involvement

2:41

of the brain stem.

2:41

We already saw the cortex

2:43

on the axial T2 weighted images,

2:45

but you can see that there

2:46

is tonsillar herniation.

2:47

So, once you get enough swelling

2:48

that you start to see tonsillar herniation,

2:51

then that can sway you more towards brain death.

2:56

Now, let me show you the SWI images.

3:00

The SWI images have this unusual pattern

3:04

where you see susceptibility and blooming

3:07

all throughout the sulci

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and basal cisterns and in the region of the

3:15

perforating vessels, coming up into the basal ganglia,

3:19

and in the region of the deep medullary vein.

3:21

So, basically,

3:21

it's throughout the arterial

3:23

and venous structures,

3:25

and this is consistent with

3:27

increased oxygen extraction,

3:29

maybe some venostasis.

3:32

And this is much more suggestive of brain death

3:37

than of patients who have cerebral edema

3:39

who will recover.

3:40

It's not as specific as no arterial

3:43

enhancement in the brain,

3:44

but it is much more predictive than just gyral swelling

3:48

and restrictive diffusion.

3:50

This patient also had some hemorrhage

3:52

in the brain stem.

3:54

And then lastly,

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I'm going to show you some perfusion images.

3:58

These are arterial spin labeling perfusion images,

4:03

and basically,

4:05

you don't see any signal in the brain,

4:09

and that's because there's basically

4:11

no significant or severely delayed perfusion

4:14

to the brain.

4:15

So, in summary,

4:17

this is a case of brain death where we saw

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diffuse swelling of the brain,

4:21

diffuse areas of restricted diffusion,

4:24

diffuse susceptibility throughout the vessels,

4:26

consistent with venous stasis and oxygen extraction,

4:30

no perfusion to the brain,

4:32

and very poor gray-white differentiation on the

4:35

non-contrast CT in a patient who had the

4:39

clinical scenario of brain death with coma,

4:42

no brain stem reflexes,

4:44

and no ability to breathe on his own.