0:01

So this is a child who presented with left orbital inflammation

0:07

and was being evaluated for the potential for orbital

0:11

cellulitis. Again, the study is done post-contrast.

0:16

As we scroll up from below, we come

0:19

into our images of the orbit.

0:22

We notice that there is swelling at the junction between the

0:26

orbit and the nasal region and lots of edema on the left side.

0:32

More importantly, however,

0:34

is that the orbital fat on the left side and the medial

0:38

aspect of the orbit has been infiltrated.

0:41

So we've crossed the medial aspect of the nasal septum.

0:46

So we're in the post-septal space and we see that there is

0:52

indentation of the medial rectus muscle on the left side compared

0:57

to the right side where it's been lifted

0:59

away from the lamina papyracea.

1:02

So this is a patient who has orbital cellulitis and more

1:06

importantly there is this collection that is seen

1:10

displacing the medial rectus muscle.

1:12

This is what we refer to as a periorbital abscess.

1:16

Now,

1:16

it is true that this collection does not have a peripheral rim

1:21

of enhancement that we typically look

1:23

for in patients who have abscesses.

1:27

Let's just say that in this particular location, you often do

1:31

not see a peripheral rim of the wall of the abscess

1:35

even though there is this inflammatory process.

1:38

Now, some people might call this a phlegmon.

1:40

A Phlegmon is an inflammatory collection that really doesn't

1:43

have as good a wall around it as an

1:46

abscess, but still has mass effect.

1:49

And you can see that the source of this periorbital

1:53

abscess is the ethmoid sinusitis.

1:56

And this is very common in children that severe

2:00

ethmoid sinusitis can lead to a periosteal abscess.

2:06

Fortunately,

2:07

whether or not this is a phlegmon or an abscess is not all that

2:10

critical, because the treatment of this at this juncture is to

2:17

administer at least 48 to 72 hours of intravenous antibiotics

2:22

as a treatment for this, and to see whether

2:25

the patient resolves the inflammation.

2:27

If they improve, then the patient often will be discharged

2:32

and given oral antibiotics to complete

2:34

the course of the antibiotics. Going in

2:38

to operate on this type of periosteal

2:41

abscess is uncommon these days.

2:44

If it is operated upon, it's usually not done with a medial

2:48

canthotomy and drainage of the abscess.

2:51

Usually what's done is that they go in endoscopically with

2:55

no surgical marks on this child, you know, no external scarring.

3:00

Instead they go in endoscopically and clear up the

3:03

sinusitis because that is the source of the inflammation.

3:09

So again,

3:11

in these cases, including orbital cellulitis,

3:14

generally treated with intravenous antibiotics at least

3:17

for two days, and then converted to

3:20

oral antibiotics with response.

3:22

If they don't respond and or is a suggestion

3:25

that the optic nerve may be in jeopardy,

3:28

then they would do endoscopic surgery for treatment of the

3:35

ethmoid sinusitis with the feeling or the philosophy

3:39

that as soon as you get rid of the primary problem,

3:42

the secondary abscess will resolve.

3:45

Just want to point out a couple more

3:46

findings on the coronal image.

3:48

If we look at the medial rectus muscle

3:52

on the affected left side,

3:53

you see it's fatter and lower density than the

3:57

medial rectus muscle on the right side.

3:59

And I think on the coronal, you can better estimate

4:02

the size of this collection.

4:04

It's relatively small.

4:05

And the communication of that collection

4:07

with the diseased ethmoid sinusitis.

4:11

As you go further posteriorly to look at the orbital apex,

4:14

we see that the optic nerve has nice,

4:16

clean fat around it and therefore is not in jeopardy of

4:20

potentially being compressed or having

4:22

an ischemic optic neuropathy.

4:24

Occasionally, you will have inflammation that leads to a

4:27

vasculitis of the veins that can lead to ischemic optic

4:31

neuropathy without compression of the orbital apex.

4:36

But that is an uncommon feature.

4:39

Let's just take a quick look on the sagittal to see whether

4:43

there's any benefit here on the sagittal scan.

4:45

You see the inflammation along the

4:47

medial aspect of the left eye.

4:50

And you can also see on the axial scan that there's a little

4:52

bit of proptosis with the left eye bulging

4:57

out compared to the right side.