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This was a 56-year-old who was thrown from

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the motorcycle after a motor vehicle collision.

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The CT scan is quite dramatic

0:11

in that the patient has

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a large amount of blood that has collected.

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If we start from superiorly,

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we see hemorrhage along the intrahemispheric fissure

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and a small subdural collection in a parafossean

0:24

location. We also see that there is a large collection

0:29

of irregular blood products

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which is seen overlying the

0:34

right frontal and parietal

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lobes and extends to the temporal region.

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The collection we could measure,

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but it's clearly greater than 10mm

0:46

in width and therefore as a surgical candidate

0:50

actually measures 17mm.

0:52

When we look to measure the degree of midline shift

0:58

at the level of the septum plus C idem,

1:00

we see that there is 10.8 mm of midline shift

1:07

greater than the 5 mm that would normally be a

1:11

surgical criterion,

1:13

and these 2 would

1:15

suggest that the patient requires

1:17

no surgical intervention.

1:21

You notice also that there is

1:23

tissue which appears to be extending.

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The gray matter appears to be extending from

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right to left

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across the edge of the Falx

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over here, just too much gray matter here,

1:36

and this represents the Subfalcine herniation

1:40

that is due to the large collection.

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When we look further inferiorly,

1:50

we see that there is tissue

1:52

which looks unlike normal cerebellar vermis

1:56

that is crossing the edge of the tentorium.

1:59

The tentorial edge

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is seen

2:03

on the left side here

2:05

and on the right side incompletely. Seen

2:09

because there appears to be brain tissue

2:11

which is extending across from the right to the left.

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You note that the

2:18

cistern on the right side

2:20

has been displaced and the midbrain

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this is the cerebral aqueduct.

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The midbrain appears to be shifted from right to left.

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This is the area of the uncus or the amygdala

2:32

and what?

2:32

Whereas the normal amygdala is ending over here on the

2:36

left side. On the right side, we see tissue

2:39

which is effacing the cistern of the

2:43

periaqueductal region,

2:46

and so we have evidence of uncal herniation,

2:51

probably evidence of

2:54

transtentorial herniation of temporal lobe structures.

2:59

This patient

3:01

developed 3rd nerve palsy,

3:04

the so-called blown pupil.

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So a blown pupil is largely secondary to compression

3:11

of the oculomotor nerve,

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the 3rd nerve

3:14

secondary to herniation of tissue

3:18

into the perimesencephalic cistern

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where the 3rd nerve will

3:22

be coursing, and this often happens with uncal herniation

3:27

because of the numerous

3:29

neurologic complaints, the

3:32

size of the subdural hematoma

3:34

and the degree of midline shift

3:36

the patient underwent,

3:38

nor surgical evacuation of the subdural hematoma.

3:43

This is the post-operative evaluation.

3:45

You see that in point of fact

3:46

the patient had a craniotomy.

3:48

By craniotomy, we mean that

3:50

portion of the calvarium

3:53

was removed and not replaced,

3:56

so craniotomy. We replaced the bone.

3:59

Craniectomy we've removed the bone

4:03

and this allows the brain to expand outward,

4:07

rather than causing midline shift and right-left shift

4:12

you notice that the patient still.

4:13

Has an element of midline shift,

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so as we measure

4:20

here and to the septum plus idum

4:24

it now measures approximately 5mm,

4:27

whereas previously it was approximately 11mm.

4:30

So they have relieved

4:32

the midline shift.

4:34

We no longer see

4:35

very much in a way of subfalcine and

4:37

herniation of tissue

4:39

a little bit right over here

4:41

of the falx tent,

4:42

and as we look down at the

4:46

uncus,

4:47

there's dramatic improvement here. Here is the uncus,

4:50

the mediotemporal

4:52

lobe on the left side.

4:54

Here is now that tentorial edge

4:56

with no apparent impression

4:59

of the uncus, maybe a little bit over here,

5:01

but that's not that much

5:02

different from the contralateral side,

5:05

so the right side a little bit

5:08

and we have a more normal appearance to the

5:11

cerebellar tissue,

5:12

and along the tentorial edge

5:16

patient has a collection of blood along the posterior

5:20

portion of the occipital lobe

5:21

as well as on the posterior falx,

5:23

but at this juncture along with that interhemispheric

5:27

at this juncture, we'd say looks pretty good

5:30

post-operative evaluation.

5:33

This is 24 hours later.

5:37

24 hours later

5:39

we are seeing low-density areas within the anterior

5:44

medial right frontal lobe.

5:50

Those with super good eyes might

5:53

also note a low-density area in the

5:57

posterior portion of the mediotemporal

6:00

on the right side. Compared with the left side

6:04

patient still has the craniotomy

6:06

and the midline shift is still resolving

6:09

not much in a way of uncal herniation,

6:11

so let's go back

6:13

to the previous. Scan

6:15

one day

6:16

earlier. That was the immediate post-operative scan.

6:19

Now in retrospect

6:21

we might wonder

6:22

about the low-density in the

6:24

medial frontal lobe on the right side

6:26

as well as this area of low density

6:30

more posteriorly,

6:32

what has happened?

6:34

Well, we get more clarity if we look at the MRI scan

6:38

and this MRI scan

6:39

was performed

6:41

48 hours after surgery.

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This is the diffusion-weighted scan.

6:47

48 hours after surgery.

6:49

Remember for diffusion-weight imaging. It's our best

6:53

sequence to look for infarcts.

6:57

What do we see?

6:58

We see high signal intensity in the medial

7:01

temporal lobe

7:02

extending to involve the occipital cortex

7:08

on the right side

7:10

as we proceed further superiorly,

7:13

we are seeing

7:13

areas on the posterior cingulum and parietal lobe

7:17

as well as the medial frontal lobe of infarction.

7:26

There's also an area over here' that will deal with

7:28

that is really related to susceptibility artifact

7:32

what happened?

7:34

This is an example of one of the complications of

7:39

head trauma that leads to a secondary injury.

7:43

This patient's subfalcine herniation

7:47

led to compromise of the anterior cerebral artery,

7:51

leading to infarction

7:52

of the medial aspect of the right frontal lobe.

7:55

This patient's

7:57

uncal herniation and transtentorial herniation

8:02

led to compromise of the posterior cerebral artery

8:06

as well as potentially the anterior choroidal artery

8:08

leading to infarction of the medio temporal lobe

8:12

as well as the occipital lobe

8:15

despite almost

8:18

immediate evacuation of this collection.

8:21

So infarctions of

8:23

occipital lobe, temporal lobe, and frontal lobe

8:29

demonstrate on the

8:32

diffusion-weighted scan and ADC maps

8:35

affecting medial frontal lobe,

8:38

parietal lobe,

8:39

portions of occipital lobe, and even the temporal lobe

8:43

from the vascular complications of herniation.