0:01

We've gotten a little introduction to the CT

0:04

findings on traumatic brain injury, but I did want

0:07

to talk about traumatic brain injury in general.

0:10

This is a very common indication

0:12

for CT scan in the emergency room.

0:16

Ranks up there with headache and new neurologic deficit

0:19

as one of the top three, as well as mental status

0:23

changes in being found down or alcoholism, for which

0:27

we often do scanning as well, trying to figure out

0:30

why the patient is having neurologic deficits. So,

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10 million people are affected worldwide in the 20 to 40-year

0:39

age group. This accounts for a lot of the deaths.

0:43

Unfortunately, in our current situation, we see a

0:46

lot of suicide attempts, and we're seeing a lot of

0:49

deaths from coronavirus in this age group as well.

0:52

But prior to the coronavirus era, traumatic brain

0:56

injury was the most common cause of neurologic

0:59

deficits in the 20 to 40-year-old age group.

1:02

And concussion is all the rage.

1:05

I mean, we see this on the football

1:06

fields, we see this on the soccer fields.

1:09

It is a consideration for a lot of our young citizens.

1:15

When we think about traumatic brain injury,

1:17

we think about two different sort of time frames.

1:20

There's the primary event, which occurs

1:22

at the time of actual impact, be it a car

1:25

accident, or a fall, or a gunshot wound even.

1:29

And that is the primary injury with laceration,

1:33

subdurals, epidural hematomas, etc. And we

1:35

talk about coup versus contrecoup injury.

1:38

The coup is at the site of impact, and

1:41

the contrecoup is the opposite side.

1:43

So if you're hit in the left frontal region,

1:46

not only can you injure the left frontal lobe,

1:49

but you might also affect the right parietal

1:52

lobe as the contrecoup location of injury.

1:56

The brain, remember, is sloshing back and forth

1:59

in the subarachnoid space, the cerebrospinal

2:02

fluid, and therefore it can bang forward

2:05

and then have a repercussion, if you will,

2:08

in the opposite direction for the contrecoup injury.

2:11

However, what may kill the patient is not

2:15

their initial injury, but what happens

2:17

afterwards, and that's the secondary injury.

2:20

Most of the time, the brain responds stereotypically

2:24

to most insults, and that is that it swells up.

2:27

And if you swell up your brain in the

2:29

confined quarters of your calvarium, then

2:33

all that subarachnoid space gets pushed out.

2:36

Instead, the brain is pushing against bone and

2:41

can injure itself in that way or can lead to

2:44

herniation, either downward or from one side

2:47

to the other side.

2:49

This pressure can lead to hydrocephalus (HC), and the

2:53

trauma itself, with fractures, can lead to CSF leakage.

2:58

When you have CSF leaking into your mastoid air cells,

3:01

or leaking into your middle ear, or leaking into your

3:04

paranasal sinuses, you can get secondary meningitis.

3:08

When those sinuses fill up with

3:11

inflammation, or sinusitis, or otomastoiditis.

3:14

So, CSF leakage and secondary meningitis may also kill

3:19

the patient. That occurs later on after the primary injury.

3:25

So, when we talk about trauma, I'm going

3:27

to be referring to one of the Bibles of neurosurgery,

3:31

Youmans and Winn Neurologic Surgery.

3:35

And it's in its eighth edition, I think,

3:37

and that's almost as popular as—not Youmans,

3:41

but Yousem's Neuroradiology: The Requisites, originally

3:45

written with my great mentor Bob Grossman, and now

3:48

with the primary first author Rohin Nadgir.

3:53

In Youmans, you will find that the indications

3:56

for surgery when you're looking at a

3:58

parenchymal mass, a parenchymal hematoma, or

4:01

what we call IPH, intraparenchymal hemorrhage,

4:06

are these extensive neurologic

4:08

symptoms that are progressive.

4:11

Any lesion greater than 50 cc's in

4:13

volume should be treated operatively.

4:17

And the way they calculate—the

4:18

neurosurgeons calculate—the volume is length

4:22

times width times height divided by 2.

4:25

So if you have a 5-centimeter hematoma by

4:28

6-centimeter hematoma by 4-centimeter hematoma,

4:31

you have 120 cc's. You divide that by 2—that's 60 cc's.

4:37

If it's over 50 cc's in volume, that suggests

4:40

that the patient should be treated operatively.

4:43

The other thing that they look at is the Glasgow Coma

4:45

Scale and how badly the patient's doing on that.

4:48

I'll show you that in just a moment.

4:50

Or things that cause midline shift.

4:53

Remember, I told you that a midline shift from a

4:55

parenchymal hemorrhage of greater than 5 millimeters

4:59

will often push the neurosurgeons to intervene

5:03

directly and relieve that pressure effect on the brain.

5:09

Here is the Glasgow Coma Scale.

5:11

You don't have to memorize this.

5:13

You just have to understand that the lower the

5:16

Glasgow Coma Scale, the worse off the patient is.

5:19

If they can't open their eyes, they can't

5:21

respond verbally, they have no motor response to

5:23

pain or whatnot—that's pretty severe disease.

5:28

And these are the different things that they check:

5:30

the eyes, the verbal response, and the motor.

5:33

Non-surgical traumatic intraparenchymal

5:36

hemorrhages are hemorrhages that are,

5:38

again, less than 50 cc's, less than 5

5:40

millimeters of midline shift, and they don't

5:43

have progressive neurologic compromise.

5:46

They don't have evidence of increasing intracranial

5:49

pressure and no mass effect on the CT scan.

5:53

These patients will be monitored with serial scanning.

5:57

You'll see the scans every 6 hours,

5:59

6 to 12 hours, and they will be monitored in

6:02

the neurosurgical intensive care unit.