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This is a wonderful illustrative example of

0:04

some pathology that I want to point out.

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So, this was a patient who had a fall from a ladder and

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had extensive soft tissue injury to the scalp.

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That was demonstrated, as you can see, more posteriorly,

0:20

both on the right side and the left side.

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You'll notice that the patient has

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some surgical staples here,

0:26

which are from the correction of the lacerations that the

0:30

patient had and has active hemorrhage in the scalp.

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However, as you scroll through here,

0:37

you'll notice that there doesn't seem to be all that much

0:40

with regard to the brain injury

0:44

despite the scalp abnormality.

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This is a case where you have to be pretty

0:51

sharp to pick up the abnormality.

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I'm going to go from the thick

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sections to the thin sections,

0:58

and I'm happy to report that I detected the abnormality

1:05

at the time of the original CT scan.

1:09

And what one sees is just a small amount

1:13

of intraventricular hemorrhage,

1:16

and it seems to be just on the left side.

1:19

So, how is it that a patient who has had significant head

1:24

trauma is showing just a small amount

1:28

of intraventricular hemorrhage?

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Well, this is a Yousem pearl.

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If you see intraventricular hemorrhage and no other

1:38

area of hemorrhage in the brain to explain it,

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the reason for the hemorrhage is a shearing injury

1:46

of the corpus callosum.

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Now, I can't demonstrate for you that

1:50

shearing injury of the corpus callosum.

1:52

You may wonder,

1:53

is it a little bit low density here

1:56

in the corpus callosum at the top?

1:59

I cannot demonstrate it,

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but I can assure you that on subsequent MRI scans,

2:05

you will find a shearing injury of the corpus callosum

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if you have a patient with head trauma that

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only has intraventricular hemorrhage.

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Sometimes you'll see intraventricular hemorrhage in

2:17

association with a parenchymal hemorrhage that

2:20

perforates into the ventricular system.

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Or sometimes you'll have blood in the ventricles

2:27

in a patient who has diffuse subarachnoid hemorrhage

2:30

and it gets resorbed into it.

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In this case,

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we don't see any subarachnoid hemorrhage.

2:33

We don't see a subdural hematoma.

2:35

We don't see a parenchymal hematoma.

2:37

All we have is a small amount of intraventricular

2:40

hemorrhage. When you see that,

2:42

order an MRI with susceptibility weighted

2:46

imaging on this patient.

2:48

Let's check the MRI.

2:50

On your MRI scan,

2:53

you want to look at the susceptibility weighted images.

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Why is that?

2:59

Subtle hemorrhage may be missed on fast spin echo scanning

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because of the refocusing 180 degree pulses with fast

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spi echo imaging that actually leads to decreased

3:13

sensitivity to blood products.

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This, although there is motion artifact,

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this is our patient's susceptibility weighted scanned.

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And what one sees is the hemorrhage that was

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detected on the CT scan in the ventricle.

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Not only that, but as we go further superiorly,

3:33

sure enough, as Dr. Yousem predicted,

3:37

there is this dark signal intensity at the top of the

3:40

corpus callosum and in the splenium

3:42

of the corpus callosum.

3:44

This is deoxyhemoglobin demonstrated on a susceptibility

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weight scan within the top of the corpus callosum

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and splenium of the corpus callosum,

3:54

identifying this patient as having had

3:56

a significant shearing injury that tore

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the largest white matter tract in the brain,

4:02

the corpus callosum.

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You'll also note on the susceptibility wade scan that there

4:07

are additional areas of dark signal intensity here at the

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gray white matter junction in the right frontal lobe,

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in the left parietal lobe, in the left occipital lobe

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and more superiorly in the frontal lobe,

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again, at the typical location for a shearing injury,

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the gray white junction,

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which we'll talk about shortly when we talk about

4:31

rotational injuries and diffuse axonal injury.

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But my point really was to remember

4:38

intraventricular hemorrhage,

4:40

isolated intraventricular hemorrhage in the face of head

4:44

trauma is due to a tear in the splenium of the

4:48

corpus callosum.

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Until proven otherwise, recommend MRI.