0:01

Let's finish up on the orbital trauma with a

0:03

few of the nuances about orbital fractures.

0:06

I mentioned orbital apex fractures.

0:08

They have jeopardy to the optic nerve because

0:11

of hematomas and therefore surgical

0:13

intervention may be required.

0:15

Sometimes this just requires a

0:17

lateral canthotomy. That is

0:19

a simple procedure along the lateral portion of

0:23

the orbit and the globe and that releases

0:27

the tension that allows expansion of a hematoma

0:31

outwardly and decreases the pressure on

0:33

the optic nerve. If, on the other hand,

0:36

there's a bone fragment against the

0:37

optic nerve, they will go in for that.

0:39

I mentioned the orbital roof fracture importance

0:41

because of the potential for dural

0:43

tears leading to CSF leaks,

0:45

meningitis, and potentially the patient

0:48

who has an epidural abscess.

0:51

When you see enophthalmos, one globe inwardly

0:55

displacement, the degree of that displacement

1:00

may push the hand for surgical intervention

1:02

for repair of the orbit.

1:04

So that way the patient is not likely to

1:06

have a permanent deficit in that way.

1:09

Retrobulbar hematoma, most often is seen

1:12

as just strandedness in the retrobulbar fat.

1:15

We only get concerned about that if the optic

1:17

nerve is displaced or if there is obliteration of

1:21

the fat around the orbital apex where the

1:24

optic nerve may be at its most vulnerable.

1:27

You can also see hematomas

1:29

outside the muscle cone.

1:31

So usually when we're referring to the

1:32

retrobulbar hematoma, we're talking about in

1:35

the muscle cone. In this case, you see hemorrhage

1:38

outside the muscle cone. So extraconal hematoma,

1:41

which is in the superior lateral portion of the

1:44

orbit, and you can see that on

1:46

this sagittal reconstruction.

1:48

So lots of swelling here and then a hematoma

1:51

outside the muscle cone.

1:53

This is less dangerous than those inside

1:57

the muscle cone at the orbital apex.

2:00

Now, let's look at some more

2:01

crazy traumatic injuries.

2:03

Here we have a patient who has obviously

2:06

extensive hematoma in the retrobulbar

2:10

compartment. You see the sagittal reconstruction.

2:13

You see the, in this case, proptosis of the globe

2:18

compared to the contralateral side.

2:19

Again, when you see this globe sticking straight out

2:23

here, you want to make sure you look for the

2:26

integrity of the optic nerve, because as it

2:30

is unfettered, it will potentially lead to

2:34

greater proptosis, put greater

2:35

strain on the optic nerve.

2:37

And in this situation, here was the optic

2:40

nerve with the optic nerve avulsion.

2:44

In other words,

2:45

the optic nerve is no longer

2:47

attached to the globe

2:49

on this lower right-hand image. Lots and lots of

2:53

retrobulbar hematoma, as well as extraconal

2:55

hematoma with the proptosis.

2:58

Here is muscle avulsion.

3:00

I talked to you about the nerve

3:02

being avulsed from the globe.

3:03

Here we have the medial rectus muscle and all

3:06

of a sudden, we're missing a segment of it.

3:08

Here is the attachment to the medial aspect of

3:12

the globe but the muscle has been ruptured.

3:15

That's something, again, seen

3:16

on the soft tissue windows.

3:17

Look at the very thin section images to

3:21

identify that the muscle is no longer

3:25

intact and has lost its integrity.

3:27

Muscular avulsion of the medial rectus muscle.

3:31

Notice that the muscle is edematous.

3:33

That's in part edematous but in part, because the

3:36

muscle contracted back on itself and that's why

3:39

it looks thicker compared to the

3:42

normal side on the right side.

3:44

Some of the complications of orbital

3:46

trauma include post-traumatic CC fistula, and

3:49

this is usually when there is orbital apex

3:52

fracture or involvement of

3:54

the lateral orbital wall.

3:56

And what one sees in the situation of a CC

3:59

fistula is that when you do a CTA, and which should

4:03

be just in the arterial phase, you see

4:06

opacification of veins and / or

4:09

the cavernous sinus itself.

4:11

So in the arterial phase, we shouldn't be

4:13

seeing venous structures. In this case,

4:15

you're seeing opacification of the

4:19

cavernous sinus and adjacent veins, as

4:21

well as the superior ophthalmic vein.

4:24

So there is a communication between

4:26

the artery and the vein, such that the

4:29

veins are seen in the arterial phase.

4:31

So a post-traumatic CC fistula.