0:01

This was a patient who got hit in the

0:03

face with a bag of bricks, frankly.

0:07

And this patient has quite a few fractures.

0:11

And we're going to keep coming back to this case

0:14

because it's a nice example of a patient who

0:16

has multiple facial fractures of

0:18

various types. But for now,

0:20

we're going to concentrate on orbital fractures.

0:24

So once again, for the fractures,

0:26

we're going to go to the thinnest section images.

0:29

In this case,

0:29

we want the 0.5 millimeter thick sections

0:33

and to scroll through them.

0:34

You could do an initial evaluation with 3 mm,

0:38

but for the medial orbital wall,

0:41

lamina papyracea in particular,

0:43

I find that looking at the thin sections is really

0:46

worth the extra time. So, general overview,

0:50

we see that there are multiple fractures.

0:51

Now, let's go through them individually.

0:54

For orbital fractures,

0:55

you can sort of think in terms of, all right,

0:57

is the orbital floor, medial wall, lateral wall,

1:02

superior wall, are they all fractures?

1:04

And you can think of it in those terms.

1:06

Suffice it to say that the orbital floor and the

1:09

medial orbital wall are the ones that are most

1:11

commonly fractured with trauma.

1:14

But the lateral orbital wall is involved in our

1:17

tripod fractures or trimalleolar fractures that

1:20

we'll talk about in just a moment.

1:21

In any case, let's start with the axial scans.

1:24

And for this purpose of looking

1:26

for orbital fractures,

1:27

we're just going to look at the

1:28

bone windows for now.

1:31

So as we scroll upward from below,

1:33

we will come into some fractures which

1:36

are involving the maxillary antrum,

1:38

which for now we're going to ignore.

1:40

On the axial scans,

1:42

you have to recognize that the top of the maxillary

1:46

antrum is going to be the floor of the orbit.

1:49

So I'm always very conscious

1:51

of looking for this structure.

1:53

This structure right here is our infraorbital

1:56

foramen. Right here. And on the other side,

1:59

you can see it right here.

2:01

Since the infraorbital foramen, which transmits

2:04

the infraorbital nerve, marks the orbital floor.

2:08

We use that as our marker for whether or not

2:11

the orbital floor is fractured

2:12

on an axial scan.

2:13

So, here I can see that there is a fracture

2:16

segment just lateral to the infraorbital

2:20

foramen. And in point of fact,

2:22

this infraorbital foramen has a line going

2:24

through it, that shouldn't be there,

2:26

recognizing that as a fracture,

2:28

compared that to the contralateral side.

2:30

Even on the contralateral side, which looks fine,

2:33

we do see a small line coming to the

2:36

infraorbital foramen, medially,

2:38

which we'll check out and see whether

2:40

that represents a fracture.

2:41

So orbital floor fracture is sometimes tricky.

2:43

On the axial scans,

2:45

we will have the benefit of the

2:46

coronal reconstructions.

2:47

Here we can see another fracture more medially,

2:52

and that is going towards the

2:54

lacrimal apparatus.

2:55

Here's our nasal lacrimal duct with

2:58

fractures there. When we look at

3:00

the lamina papyracea,

3:03

we want to look at this.

3:05

And we note that there is some depression

3:08

of the lamina papyracea on the right side.

3:12

And we can see, on the left side,

3:14

there is outward disruption.

3:16

We have a little fracture fragment

3:18

protruding on the left side.

3:22

We notice also on the lateral aspect of the

3:26

orbital wall, that the lateral wall on the

3:30

left side has a comminuted fracture.

3:33

So, so far we've got the orbital floors,

3:36

we've got the lamina papyracea bilaterally.

3:38

Let's look at the orbital roof.

3:40

Here we are coming up to

3:41

the top in the orbital roof.

3:43

So that seems as if there's sparing of the orbital roof.

3:47

So we've made a pretty good sense of things we

3:50

can ignore for right now, the nasal bones.

3:51

But we'll come back to all those

3:53

other additional fractures.

3:54

We notice also that the maxillary antrum

3:58

has an air-fluid level within it.

4:00

And it's likely that that's going

4:02

to be the blood products.

4:05

I'm going to just quickly look on the soft tissue

4:08

windows to demonstrate the globes.

4:11

And as you can see,

4:13

the patient has lens implant

4:15

here and lens implant here.

4:17

But the anterior chamber looks fine on both sides.

4:21

No blood, no shallowness. The vitreous looks fine.

4:24

So I've shown you cases where the globes are

4:27

all traumatized and there's no fractures.

4:30

Here's a case where there's all kinds of

4:32

fractures and yet the globes themselves are perfectly fine.

4:36

And if you look at the retrobulbar

4:38

space and the intraconal space,

4:40

there's really no strandedness or hematoma

4:43

to really to speak of behind the globes.

4:46

That's one of the curious things about orbital

4:49

injury. Now, let's look on the coronal images.

4:52

So anytime you see air in the orbit,

4:56

we're going to use the term orbital emphysema.

4:58

I use little droplets of air to focus my attention

5:04

on adjacent bone, because you want

5:07

to know where that air came from.

5:09

It's likely that it came from a fracture very close by.

5:12

So let's magnify this a little bit and get into

5:16

it. All right, so we'll start with the left globe.

5:20

We have orbital emphysema.

5:23

We have the infraorbital foramen.

5:26

We have the fracture that we worried

5:29

about. It's very subtle here,

5:30

but it is present going towards

5:35

the infraorbital foramen, you see a tiny little

5:37

drop of air. That's my little marker.

5:40

Look very closely at this bone just above it, because

5:43

it's offset a little bit and there's discontinuity.

5:47

So the orbital floor here is fractured.

5:50

And use the little droplets of air that you

5:53

see to focus your attention and lower your

5:57

threshold for calling it fractured.

5:59

We see that the lateral orbital wall has that comminuted

6:01

fracture. Here's a focus of air, right?

6:06

What's it doing there?

6:07

Here is a discontinuous area where there has

6:11

been fracture of the lamina papyracea.

6:14

So little droplets of air, always look adjacent and

6:19

look for hemorrhage, and look for fractures.

6:21

So here again,

6:22

discontinuity of the lamina

6:24

papyracea on the left side.

6:26

And we'll deal with the other fractures when we

6:28

come back to the nasal orbital ethmoid or NOE fractures

6:32

I want to point out one structure which is

6:34

often misunderstood as a fracture or site,

6:38

and that is the entry of the ethmoidal artery.

6:42

So the anterior ethmoidal artery canal is seen

6:47

here, and here on the right and left side.

6:50

Those are not fractures. That's not depression.

6:52

That's where the artery,

6:54

the anterior ethmoidal artery comes in.

6:56

If you go further posteriorly,

6:59

you will find a second area right here,

7:01

which is the posterior ethmoidal artery entry.

7:04

Okay, let's look on the right side.

7:07

So on the right side, here's our infraorbital

7:10

foramen. And again,

7:13

some discontinuity here without displacement.

7:17

You can see a tiny little drop of air here.

7:19

Tiny little drop of air here.

7:21

That's in the offset, that's the fracture.

7:24

The anterior rim here has been fractured, as well.

7:29

Let's look at the lamina papyracea.

7:31

I'm looking for any little droplets of air.

7:33

Lamina papyracea, we're going to pass.

7:37

And the lateral orbital wall, we're going to pass.

7:40

So just a nondisplaced fracture of

7:43

the orbital floor on the right side.