0:00

So this patient also presented with a fever

0:03

and pain involving the left side of his mouth.

0:06

And when we look at the contrast-enhanced CT

0:08

scan, we see an obvious abnormality involving the

0:10

posterior aspect of the left floor of mouth extending

0:13

into the anterior portion of the tongue base.

0:16

And again, as we've mentioned

0:17

before, anatomy is so key.

0:19

So we have a muscle again that

0:20

goes in the genial tubercle,

0:22

that extends posteriorly to the tongue base.

0:24

The tongue base are these transverse muscles.

0:26

So because this mass is predominantly involving the

0:29

floor of the mouth, we know that we will place this

0:32

in the floor of mouth as opposed to the tongue base.

0:35

When we look at the contrast-enhanced CT,

0:37

we see this subtle area of enhancement

0:39

surrounding this cystic fluid collection.

0:42

So if we just look at the images alone,

0:44

this could be a couple of things.

0:46

First of all, if possible,

0:47

this could be an epidermoid.

0:49

It could be any other type of congenital lesion,

0:52

like a dermoid, but the fact that it's fluid

0:55

and the patient has a fever — that suggests that

0:59

we're dealing with a floor of mouth abscess.

1:01

Also, if you look more posteriorly, we can see

1:04

some edema surrounding this fluid collection.

1:07

So this tells us that this is a floor

1:09

of mouth abscess with some surrounding edema.

1:12

Typically, floor of mouth abscesses arise from a rotten

1:15

tooth, so typically they're odontogenic in origin.

1:18

And oftentimes we'll see these fluid-filled

1:20

collections directly abutting the lingual cortex

1:24

of the mandible, suggesting they are arising

1:26

from an inflamed or, if I will, a rotten tooth.

1:30

But in this case, this is centered within the

1:32

posterior aspect of the floor of the mouth.

1:35

So this is just the typical appearance of a classic

1:37

case of a floor of mouth abscess, characterized

1:41

by the internal fluid collection, the thin

1:43

enhancing rim, and also some surrounding phlegmon.