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Hello and welcome to Noon Conference, hosted by MRI Online

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Noon Conference connects the global radiology community

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through free live educational webinars that are accessible

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for all and is an opportunity

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to learn alongside top radiologists from around the world.

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You can access a recording of today's conference

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and previous noon conferences

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by creating a free MRI online account.

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Today we are honored to welcome Dr.

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eSSH McCury for a lectured entitled Anatomy

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and Pathology of the Oral Cavity.

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Dr. McCury received his undergraduate degree from Duke

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University and an MD degree from Georgetown University.

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He currently holds appointments at multiple institutions

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and is a devoted educator who's been an invited speaker on

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over 500 occasions and has written

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and edited 15 textbook textbooks.

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He's a consulting editor for both neuroimaging clinics

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and Magnetic Resonance Clinics of North America

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and Associate editor for the Journal

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of Computer Assisted Tomography.

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We are thrilled he's here today to share his expertise

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At the end of the lecture, please join him in a q

1:01

and a session where he will try to answer as many questions

1:04

as we can before our time is up.

1:06

Please use that q and a feature to put those questions in.

1:09

With that, Dr. McGee, over to you.

1:13

Yeah, thanks for having me.

1:14

Um, again, thanks to MRI online modality.

1:18

It's always a privilege and an honor to be here.

1:21

Um, Ashley kind of joked, um,

1:23

and said, uh, we'll take as many questions as you can.

1:26

I'll take as many questions as they'll allow me to take.

1:29

I have a free afternoon.

1:30

I have plenty of time to, to uh, prepare for this.

1:33

So if you have any questions, just let me, let me know.

1:36

And, uh, again, thanks a lot to the team

1:38

and thanks all of you for joining.

1:40

Um, I've been working with, uh, modality, uh, uh, for,

1:44

I dunno, five, six years

1:45

and it's just a terrific, terrific

1:46

team, terrific organization.

1:48

Uh, and so Ashley and, and the whole team, uh, Jackie

1:52

and uh, and Ben, thanks so much.

1:54

Um, what I'm gonna talk today is I'm gonna talk about

1:57

anatomy and pathology of the oral cavity.

2:00

Um, and you'll have to excuse me

2:02

'cause I've been traveling a fair amount and I,

2:03

and I have a bit of a cold,

2:05

so if I sound a little raspy, that's me.

2:07

So I'll do my best. And I have my water here as well,

2:10

but this is a brand new lecture on anatomy

2:12

and pathology of the, of the oral cavity.

2:16

And what we decided to do is

2:18

that we're gonna give a two-part series

2:20

and the first part is gonna be on the oral cavity

2:23

and the second part is gonna be on the oral pharynx.

2:25

And that's gonna be held sometime in October.

2:29

But today we're gonna take a real deep drill down

2:31

into the oral cavity.

2:33

And the reason why I like this format so much is

2:36

because, you know, I've been doing this, I hate

2:38

to say lecturing since the last century.

2:41

And what I've seen is that the talks get shorter and shorter

2:43

and shorter when we go to our annual meetings.

2:46

And as a result, um, either there we don't get as much time

2:49

to really teach, um,

2:52

or we try, when you go to these meetings,

2:54

sometimes they're taking 30 to 45 minutes of information

2:57

and trying to distill it into 15 or 20 minutes.

3:00

And you know, part of the challenge now is you're just

3:03

trying to get through the talk.

3:04

So what, what we're gonna do over the next, uh, 15 minutes

3:08

or so is really spend a lot of time going over the anatomy.

3:12

And this is not gonna just be focused on cancer,

3:14

it's gonna be focused on the anatomy.

3:17

And we're also going to give you a differential diagnosis

3:20

for some of the most common things

3:21

that we'll see in the oral cavity.

3:24

So the first thing that we're gonna start off

3:26

with is the anatomy of the oral cavity.

3:29

So the oral cavity really is comprised of about seven areas.

3:32

Now, really depends on who you read the actual numbers,

3:37

but in general we consider the lip the buccal mucosa,

3:42

which is basically the undersurface of the lip, the floor

3:46

of the mouth, the alveolar ridge, the hard palate,

3:49

the oral cavity, and the retromolar trigone.

3:51

And we'll go over all these in great detail.

3:54

The anterior

3:55

or the, I should say the posterior margin

3:58

of the oral cavity is formed by this papilla here,

4:02

which is the circum valley papilla.

4:04

So everything anterior

4:05

to the circum valley papilla is in the oral cavity.

4:09

The roof of the oral cavity is formed by the hard palate.

4:13

The inferior portion

4:14

of the oral cavity is formed by the floor of the mouth.

4:17

And as I mentioned before,

4:19

the anterior portion is essentially formed by the lip.

4:22

Now these are all, um, illustrations

4:25

or examples about pathology involving the different

4:29

subsides of the oral cavity.

4:30

Again, we'll go through this in great detail,

4:33

but I did want to emphasize this tumor's located

4:36

in the buccal region.

4:37

And I'll tell you why I used the term now buccal region.

4:41

The next is in the floor of the mouth.

4:44

This is an example of the alveolar ridge.

4:47

This sagal image is an example of the heart palate.

4:51

This image is an example of the oral tongue.

4:54

And this is an area of the retromolar trigone, which is

4:57

behind the last molar.

4:59

And again, we'll go over all this in detail,

5:01

but this is just a snapshot

5:03

of everything we're gonna cover in the next

5:06

15 minutes or so.

5:08

So the first area that we'll talk about

5:10

is the buccal region.

5:12

Now if I was giving a talk on the spaces of the head

5:15

and neck, then I'll use the term the buccal space.

5:18

Now literally just, you know, I've been doing this now

5:20

for 30 years, but you know, over the last year

5:22

or so I've now sort of changed how I approach this.

5:26

Um, and the terminology that I use.

5:28

And a lot of it is just the fact that I get to see patients

5:31

and examine patients once a week in the head

5:35

and neck oncology clinic.

5:37

So when we are examining patients, we tend not

5:40

to use the term buccal space,

5:42

but rather the surgeons talk about this sulcus right here,

5:45

which is a gingiva buccal sulcus.

5:48

So the ging of a buccal sulcus is located

5:50

right where my arrow is.

5:52

And then as you go laterally, then we extend into

5:55

what we call the buccal space.

5:58

But from a clinical standpoint, the majority of pathology

6:00

that I see is not necessarily in this true buccal space.

6:04

Rather it's in this area, the gingival buccal sulcus.

6:08

So I'm sort of now referring to this as the buccal region.

6:11

So the buccal region is formed by this mucosa right here,

6:15

which is located on the lateral margin

6:19

of the alveolar ridge and the mandible.

6:22

And that is the gingiva.

6:23

So I'm sure all of you know about the gingiva.

6:26

This is sort of how you brush your teeth

6:28

and if you're not brushing your teeth,

6:30

you're probably getting, uh,

6:31

gingivitis if you will, with the little bleeding.

6:34

So make sure you brush your teeth twice a day, right?

6:36

So that's the gingiva.

6:37

Now, right lateral to this on the medial surface

6:41

of the lip is the buccal area or the buccal mucosa.

6:45

So this buccal area is on the undersurface of the lip.

6:49

Now as you know, if you take your finger

6:52

and you stick it between your cheek

6:54

and your gum, you can go ahead

6:56

and do that if you want to, I'm not gonna look,

6:57

I'm not gonna have you turn on your cameras,

6:59

but if you suppress it all the way down to the deep area

7:03

where you stop, basically where the gingival

7:06

and the buccal area meet is referred to

7:08

as the gingival buccal sulcus.

7:11

And these are the common areas for tumors

7:14

to involve this buccal area.

7:16

So one of the misnomers that I've done in the past is

7:19

that we talk about buccal space or buccal region cancers

7:22

and we talk about buccal squamous cell carcinomas.

7:25

So as you'll see in the slides that are coming up,

7:28

these squamous cell carcinomas tend

7:30

to occur in this gingival buccal region

7:32

or the gingival buccal sulcus.

7:34

And then these other pathologies arise in the buccal space.

7:38

So we talked about this anatomy,

7:40

which is the gingival buccal sulcus.

7:42

But the other piece of anatomy in the buccal space is

7:45

for instance, this muscle right here,

7:47

which is the bator muscle.

7:49

And this extends posteriorly into an area

7:52

of the tegal mandibular RAF vein.

7:54

We'll talk about that later as we extend out laterally.

7:58

Now we get into the subcutaneous fat,

8:01

this little vessel right here is the facial vein.

8:03

And then we have this swooping structure that is contiguous

8:08

with the parotid gland that pierces the buccinator muscle

8:12

and extends into the gingival buccal sulcus at approximately

8:15

the level of the second molar.

8:17

And this is the parotid duct.

8:19

Now if you look at the buccal space,

8:21

there's this superficial buccal fat and this deep buccal fat

8:25

and that demarcation is essentially

8:28

provided by where this parotid duct is located.

8:31

If you look a little bit more lateral and it's hard to see,

8:35

but you can have these small superficial muscles

8:37

of facial expression

8:39

and just lateral to this are gonna be branches

8:41

of the buccal division of the facial nerve.

8:44

Now we can't always see these normally,

8:47

but on the other hand, if we do have perineural spread along

8:50

these buccal divisions,

8:51

we can sometimes see those striations.

8:54

So this is what we, again, what I call the buccal region.

8:57

One more example here.

8:59

This is a tumor involving the gingival buccal sulcus

9:02

and just lateral

9:04

to this will be the fat involving the buccal space.

9:07

So I spent a lot of time on that.

9:09

But on the other hand, especially if you're in an area such

9:11

as in India or in other areas, um,

9:14

I know my colleague Var is on the talk call, uh,

9:17

talk right now in India they have a lot of beetle nut.

9:20

Um, in the US we have some snuff dippers.

9:23

That's where the majority of those uh, cancers are gonna be.

9:27

So this is just an example here

9:29

of squamous cell carcinoma involving the buccal region

9:32

involving the gingival buccal sulcus.

9:34

As I mentioned before, you know, I'm from India,

9:37

you know there's a lot of beetle nutt usage.

9:39

So they stick the beetle beetle nut

9:40

and they put it between their cheek and their gum.

9:43

And the United States, you know, where I grew up,

9:45

in the south we have a lot of snuff dipper.

9:47

So in order to get your nicotine fix, you take the snuff

9:51

and you put it right literally

9:53

between your cheek and your gum.

9:55

And as a result, these areas are prone

9:57

to develop squamous cell carcinoma, which is going

10:01

to be the most common tumor to involve this buccal region.

10:05

Now one of the challenges, and as I mentioned

10:07

before Wednesday's I see patients, is

10:10

that we had a couple patients yesterday

10:12

that had tumors involved in the gingival buccal sulcus.

10:15

Now the challenge is if you see something like this on

10:18

imaging, you don't really know whether it's actually going

10:22

to involve the buccal area, which is the undersurface

10:25

of the lip or if it's actually going to involve the gingiva,

10:29

which is overlying the maxilla and the mandible.

10:32

So if we're just looking like this, we have

10:34

to be somewhat nonspecific.

10:35

We can describe the tumor

10:37

and we can describe if you will, this lateral extent,

10:40

but we really don't know where it's located

10:43

and this is where that puff cheek technique comes into play.

10:47

So here's another example

10:48

of a buccal squamous cell carcinoma.

10:51

Again, we can describe this

10:52

and we can measure the size of it,

10:55

but we don't really know specifically where it is.

10:58

Now here's an example of the classic cuff cheek technique.

11:01

So what you can do if you're, if I know as radiologists,

11:05

you can't literally monitor every patient that's there.

11:09

But if you can train your technologist

11:11

to say if they do have these cancers involving, if you will,

11:14

the lip just go ahead

11:16

and have the patients puff their cheeks

11:19

and all of a sudden we can see this nice squamous cell

11:22

carcinoma, let's not nice,

11:24

but you know, the squamous cell carcinoma

11:26

that's really isolated to the lip.

11:28

And if you look real closely we can see this re re

11:32

reticulation of fat extending laterally

11:34

and compare this with the opposite side.

11:36

Notice the nice mucosa here involving the lip

11:40

and the nice fat plate on the left hand side.

11:43

Another example here, another example

11:46

of a carcinoma involving the buccal area.

11:49

This is involving the buccal surface of the lip

11:52

and also the lip itself.

11:53

So we'll just go and call this the buccal region.

11:55

But this is a true lip carcinoma

11:58

that's separate from the gingiva so you can remember

12:01

that buccal area.

12:03

Now the challenge is also is

12:06

that these buccal cancers are in a close approximation

12:09

to the lip and also the teeth.

12:13

Now I don't know about you,

12:14

but as a kid I used to eat a lot of hard candy

12:16

and some of you may have that as well too.

12:19

But one of the challenges is that if you have a lot

12:22

of amalgam involving your teeth, if you have a lot

12:25

of teeth fillings where they've used this meta with a metal

12:28

or this silver, you can occasionally have the

12:31

streak artifacts.

12:32

So one of the pitfalls that we get into as a radiologist is

12:35

that a patient will present

12:36

with a cancer involved in the gingival buccal area.

12:40

And you know, if you read this, you'll just say,

12:42

I don't see any tumor at all.

12:45

But there actually is a tumor

12:46

because you can look, the surgeons can look in

12:49

and actually see the cancer.

12:51

So one of the pitfalls

12:53

that we run into about tumors involved in the gingival

12:55

buccal region is that they can be obscured

12:58

by this spray artifact.

13:00

So this is that same patient that had a pet ct

13:04

and on the pet CT we can nicely see this cancer

13:07

that has abnormal uh, FDG uptake

13:10

located in the gingival buccal sulca.

13:13

So you know, I caution you about um, something like this

13:17

because if you say it's normal, um,

13:20

and they see the cancer, it kind of reduces our credibility.

13:23

I think it's fair to say this area is obscured

13:26

by streak artifact

13:28

and then it's really best to be evaluated clinically.

13:31

So just a little modification, how you report this

13:35

I think can increase your credibility

13:37

to your referring physicians.

13:39

Another example here, this is the second most likely tumor

13:43

to involve the buccal region

13:45

and this happens to be lymphoma.

13:47

So number one is squamous cell carcinoma,

13:50

and the second most likely tumor

13:52

to involve the buccal region is going to be lymphoma.

13:55

So here's an example of a nice lymphoma

13:57

that's involving the uh, buccal region.

14:01

This is the buccal cortex of the maxilla.

14:03

And here we can see this intermediate signal mass

14:06

that's involving the soft tissues.

14:09

Now it's rare for lymphomas

14:11

to actually arise in the buccal area itself.

14:14

Oftentimes they may be secondary extension.

14:17

This example was the lymphoma

14:18

that involves the right maxillary sinus that blew

14:22

through the maxillary sinus, through the alveolar assessed

14:26

and is involving the buccal area.

14:28

Now you look at this and you'll say, well, it sort

14:30

of looks like the sinuses.

14:31

But while always what I want you

14:33

to remember is draw a line down the middle,

14:35

compare one side to the other side.

14:37

So when we're at this level,

14:39

what we see here is the masser muscle.

14:41

This is a nice example of a deep buckle space.

14:44

And at this level we really don't see any air involving the

14:49

alveo recess of the maxillary sinus.

14:51

So when you look at this, you can see that all

14:53

of this is not the maxillary sinus,

14:55

but this is all lymphoma

14:57

that's involving the left buccal space.

15:02

Now when we talk about the buccal region,

15:05

the other common lesions that can involve this area

15:09

include things such as minor salivary gland tumors

15:12

and mesenchymal tumors.

15:14

So what I wanna do is first talk about

15:17

the mesenchymal tumor.

15:18

So this was a patient, a younger patient.

15:20

It was about a 30-year-old patient

15:21

that we ended up seeing in our head and neck clinic.

15:25

I remember this when we looked at him clinically,

15:28

it looked like a relatively small tumor

15:30

that was involving the lip.

15:32

So we were able to identify to involve the lip,

15:35

and if we look laterally we can see all this

15:38

obliteration, the fat.

15:39

So this was clinically unknown.

15:40

So we have to remember that I'll mention this extent

15:43

and also the proximity to the pro duct.

15:47

But my point in this particular case is

15:49

that when we talk about differential diagnosis

15:52

of the buccal area, you know we tend

15:55

to, you know, it's head and neck.

15:56

So we tend to get nervous.

15:57

And because it's head and neck,

15:58

it's supposed to be really complicated.

16:00

The point that I wanna make is that just realize in the head

16:04

and neck, the component tissues of the head

16:07

and neck are the same

16:08

that we see everywhere else in the body.

16:11

So if you remember I talked about this structure right here

16:14

was the vaccinator muscle, that's muscle.

16:17

We talked about this area here, which is fat.

16:19

That's fat, fat seen everywhere in the body

16:22

and we have skin.

16:24

So the majority of tumors that we're gonna see in the head

16:28

and neck arise from the component tissues.

16:31

And these component tissues are seen

16:33

everywhere else in the body.

16:35

So the number one thing is gonna be squamous cell carcinoma.

16:38

The second thing is gonna be lymphoma.

16:40

And the third thing is,

16:42

is oftentimes these little sarcomas

16:45

and these mesenchymal tumors can be seen anywhere.

16:49

So just remember when you are looking at differential

16:51

diagnostic considerations.

16:53

In the buccal space, remember you have muscle and fat

16:56

and if I showed you this for a leg,

16:58

I'm sure you could easily come up

17:00

with a diagnosis of a sarcoma.

17:02

But just realize sarcoma is a rise in the head

17:05

and neck area as well too.

17:07

Now one of the things that's kind of unique about the head

17:11

and neck is that we can have these minor

17:13

salivary gland tumors.

17:15

So it took me about 25 years to really understand this.

17:19

Like I said, I'm not the sharpest tool in the shed,

17:21

but eventually I kind of get it.

17:23

Um, what is a minor salivary gland tumor?

17:26

Well, we know that there's salivary gland tumors

17:30

and we have salivary gland structures which include the

17:33

parotid, the submandibular gland, and the sublingual gland.

17:37

If you have salivary tissue in the major glands, well

17:41

that is salivary tissue in a big gland.

17:45

But on the other hand, what happens in the head

17:47

and necks is that you can have ectopic rests

17:50

of salivary tissues that get lost, if you will,

17:54

and they end up in areas where in general they shouldn't be.

17:58

Now the certain areas do have a predilection

18:01

and one of these areas are in the buccal space.

18:04

So you can end up having the exact same type of tumors

18:08

that you can have in the parotid gland

18:10

or the submandibular gland

18:11

because that salivary tissue is there.

18:14

But if that salivary tissue is somewhere

18:16

where it shouldn't be,

18:17

so you have a tumor arising in salivary tissue

18:20

that's not in a major gland, that's

18:23

what we call a minor salivary gland tumor.

18:26

And in the buccal area there is a higher concentration

18:30

that we expect there to be.

18:32

So this is gonna be one

18:33

of those weird head and neck pathologies.

18:36

And so we have to include minor salivary gland tumors when

18:40

we see masses involving the buccal space.

18:42

And in this case it was a mu epidermoid carcinoma.

18:47

The other things that can arise here include

18:49

adenoid cystic carcinoma.

18:51

We can have pleomorphic adenomas arise here as well too.

18:55

So now is the minor salivary gland tumors that we have

18:58

to consider involving the buccal space.

19:02

The other thing in the buccal space, and this is more rare,

19:05

but if you really love head

19:07

and neck cancers, you have certain lymph nodes

19:10

that are involving face.

19:12

Now this is a specific type of lymph node

19:15

that are called facial lymph nodes.

19:17

I won't get into too much detail,

19:19

but I did want you to know there are about six

19:21

or five types of facial lymph nodes.

19:24

And this is an example

19:25

of a buccal lymph node located in the buccal space.

19:29

Again, the involvement is pretty rare in general,

19:33

when we reported and described these lymph nodes about 30

19:36

years ago, they were mostly involved

19:38

with recurrent squamous cell carcinoma, lymphoma,

19:42

and recurrent melanoma.

19:44

But this is the classical example.

19:45

In fact, with a leap of faith it almost looks rounded

19:48

and it's located in the buccal space.

19:50

So that's a buccal space lymph.

19:53

So we talked a little bit about tumors

19:55

involving the buccal region.

19:58

Now what we're gonna do is talk about some other pathology

20:01

involving the buccal region

20:02

and we'll specifically talk about infection.

20:05

Now I have the, the privilege of working

20:08

with some terrific head and neck surgeons

20:10

and also some terrific dental pathologists.

20:13

And I also have a joint appointment,

20:14

the oral maxillofacial radiologists.

20:17

And it's amazing these, uh, wonderful people know so much

20:22

about the uh, the teeth.

20:24

Um, it just makes me feel so inadequate.

20:27

So I just know a small amount.

20:29

But what I'll do is I'll just mention about

20:31

how odontogenic processes can lead

20:34

to various infections in the region of the oral cavity.

20:39

So if we look at a patient that presents such as this,

20:43

what we see here is all

20:44

of this reticulation involving the fat,

20:46

it's all involving the buccal space.

20:48

In fact, if you look real closely,

20:50

we can see a small little subperiosteal abscess.

20:54

Well, the take home message is the following is anytime

20:57

that you have an unexplained infection involving the buccal

21:00

region and the cheek, the first thing that we have

21:03

to exclude is the bug bite.

21:04

Make sure they didn't have impetigo

21:06

or they had, there was something

21:09

that they had a bite or something like that.

21:11

But if that's been excluded, just realize

21:14

that odontogenic processes

21:16

and infections that involve the teeth, if they breach

21:20

the buccal cortex,

21:22

they can extend into the soft tissues of the face.

21:25

So this is an example

21:27

of a small little odontogenic infection

21:29

that eroded the buccal cortex

21:31

and when it erodes the buccal cortex,

21:34

it extends into the soft tissues of the face.

21:37

So buccal space infections,

21:38

bottom line is they can arise from infections

21:41

involving odontogenic infections.

21:46

Here's an example of a lymphatic malformation

21:48

involving the buccal space.

21:50

Again, very, very nicely identifying the buccal space.

21:53

We can see involvement in the superficial and the deep lobe.

21:56

Again, classical appearance of a lymphatic malformation.

21:59

It's high signal on T two, low signal on T one

22:03

and is not enhanced with contrast.

22:05

In fact, if you look at this, it's not fully low signal.

22:08

The slightly high signal is probably due

22:10

to some proteinaceous material in the

22:12

lymphatic malformation.

22:14

But again, the point of this case is to identify proper

22:18

location of the buccal space.

22:22

Now you can also have some other areas

22:24

that involves the buccal region and the buccal space.

22:28

I was looking at this one case here, no history whatsoever

22:31

and I just happened to see this little area

22:33

of increased attenuation.

22:35

This is just a foreign body

22:36

that's locating the buccal space.

22:38

I never had the opportunity

22:40

to figure out what it was due to.

22:42

You know, it could be due to

22:43

I guess a rock if he was hurt in the past

22:46

or maybe a BB or something like that.

22:48

But we can see that it's located in the

22:50

fat in the buccal space.

22:52

And these are always kind of fun.

22:53

We see these a lot on sinus cts.

22:56

I remember the first time I saw this, I was kind

22:58

of taken for a loop.

23:00

I saw this oval structure

23:02

and really all this was was what we lovingly referred to

23:05

as a ible, which is basically a piece

23:08

of candy or something like that.

23:10

I think this was a a jawbreaker if you know what that is.

23:13

So this was just a piece of candy

23:15

that was located in the gingiva buckle sulcus.

23:18

I think this patient came back later about a

23:21

year and it wasn't there.

23:22

So obviously it dissolved over over the year time.

23:25

But again nicely demonstrating the

23:28

location of the buccal region.

23:30

So what we did first is we talked a fair amount

23:33

involving the buccal region.

23:35

We talked about the gingiva buccal sulcus, which is

23:38

where the majority of squamous cell carcinomas occur from.

23:42

And we talked about the buccal space

23:44

and we gave a differential diagnosis

23:46

for buccal space lesions in which we also have

23:49

to include lymphoma and minor salivary gland tumors.

23:54

Now what we'll do is move on to the oral

23:57

or the mobile tongue.

23:59

So when we look at the tongue, there's actually two parts

24:02

to the tongue and that's separated by this area right here,

24:07

which is a circum valley papilla.

24:09

So everything posterior

24:11

to the circum valley papilla is located in the tongue base.

24:15

And then we'll talk about

24:16

that when we talk about the oral pharynx.

24:18

But everything anterior to the circum valley papilla

24:22

is located in the oral tongue

24:24

and it's also known as the mobile tongue.

24:28

So when we look at the innervation of the oral tongue,

24:32

it actually has a very unique innervation.

24:35

Part of the oral tongue is supplied by the lingual nerve,

24:39

which is a sensory uh, branch of the fifth nerve.

24:44

We also have taste involving the anterior two thirds

24:48

of the tongue and the motor portion

24:50

of the oral tongue is supplied by the 12th nerve.

24:53

So just in the oral tongue you have three different nerves

24:57

providing innervation.

24:59

12 is motor, five is sensory to the anterior two thirds,

25:04

and then the cordani is the taste.

25:06

And I think all of you hopefully will remember

25:09

that from medical school.

25:11

So what's the most common tumor to involve the oral tongue?

25:14

Well, it's gonna be squamous cell carcinoma.

25:17

So again, this is not purely a talk on cancer,

25:20

but this, I just did wanna point this out that this is going

25:23

to be the most common tumor to involve the oral tongue.

25:27

Now one point that I did wanna make is

25:31

that when we are looking at oral tongue carcinomas realize

25:35

that we, it's good for us to measure,

25:38

to make a measurement on the largest size of that tumor.

25:42

And the reason is, is that this helps us with staging.

25:46

But the new eighth edition of the A JCC

25:50

is not purely based on size alone,

25:53

but there is something called the depth of invasion.

25:56

So what the depth of invasion is, is

25:59

that it is a pathologic diagnosis.

26:02

When you are measuring an oral tongue cancer like this,

26:05

it is a good idea to try to make the largest measurements

26:08

because when the surgeons look at this, they're trying

26:10

to figure out how large it is.

26:13

What ends up happening on radiology, on imaging is

26:16

that we can look in various sections, we can look in axial,

26:20

coronal and sagittal sections.

26:22

And when we look orthogonally we can actually measure

26:26

this a lateral or horizontal measurement.

26:29

This horizontal measurement is tumor thickness is

26:33

not depth of invasion.

26:35

Depth of invasion is a pathologic measurement

26:38

where the pathologist looks at the basement membrane

26:42

and what they do is they basically approximate the location

26:46

of the basement membrane and then they look deep to it.

26:50

And what they're looking for is how deep

26:53

do these tumor cells go with relationship

26:57

to the basement membrane?

26:58

So this is the basement membrane, excuse me, this is

27:02

what we mean by depth of invasion.

27:04

The challenge is the worst prognosis of depth of invasion.

27:08

The deeper it is, the higher likelihood there is a

27:12

microscopic evidence of perineural invasion,

27:16

not perineural spread but peroneal invasion

27:20

and also lymphatic VA invasion.

27:23

Also, the deeper the depth

27:26

of invasion is the higher likelihood there is

27:29

of metastases to lymph nodes.

27:32

So realize this is a histologic pathologic measurement

27:36

and tumor thickness is not the same as

27:40

as depth of invasion.

27:42

Now this is just the overall classification

27:46

when you look at this.

27:47

T one is less than two and T three is greater than four.

27:52

But once you get to levels of T two

27:54

and forces of T three, this is a combination of size

27:59

and the depth of invasion.

28:01

With the depth of invasion really being the driver,

28:04

the more depth of invasion is this tends

28:06

to push the staging higher.

28:09

And again, that's a new addition to the eighth edition.

28:11

But again, please, tumor thickness is not the same

28:15

as depth of invasion.

28:17

So when we are evaluating the oral tongue,

28:23

really the best way to look at the oral tongue is

28:26

to perform mr.

28:27

So in the United States we don't do as much Mr

28:30

as they do in other parts of the world,

28:32

specifically in Europe, uh, some parts of India

28:35

and some parts of Asia

28:37

and probably South America as well too.

28:39

You know why that's the case, it's probably multifactorial,

28:43

but I think part of it is in the US in general,

28:47

patients end up getting a a pet ct.

28:49

So they're getting a CT and they're getting a pet.

28:52

Now, personally I think you should do the CT separate from

28:55

pet, but you know, depending on where you are,

28:58

and we also have to take into factors regarding payment

29:01

for the patient because in the US you know,

29:04

we have co-payments patients, insurers differ.

29:07

So we always have to factor that in in order

29:09

to make sure we have some level of, of healthcare equity

29:13

and try to reduce our disparities.

29:16

But on the other hand, if you're in a, in a place

29:18

where money is not necessarily an issue

29:21

and let's say you have a more of an egalitarian approach

29:24

to your healthcare and how you acquire your imaging,

29:27

I think MR probably is the best way

29:29

to look at the oral tongue.

29:31

But you have to make sure that you hold rock solid still.

29:35

So this is an example of a patient

29:37

that has an oral tongue cancer

29:38

and it's really, really hard to see the tumor.

29:42

But on the other hand, when you perform the MR right here,

29:45

you can see the small little tumor

29:46

that's involving the lateral aspect of the oral tongue

29:50

that you cannot see on ct.

29:52

So again, a nice example of a tumor

29:54

that's better seen on MR than compared to ct.

29:58

Another example here,

29:59

this patient has a low volume cancer

30:02

involving the oral tongue.

30:04

Again, you can't see it because of the streak artifact.

30:07

Again, I caution you if you are looking at the ct, not

30:10

to call it normal, what you can say is

30:13

that the tumor is not seen on the CT

30:16

and can be evaluated

30:18

with direct visualization and palpation.

30:20

You can also suggest that there's no deep invasion,

30:23

which is the surgeons are looking for.

30:25

'cause typically they can see the cancer on the oral tunnel.

30:28

But I would caution you not to say it's normal

30:30

because when you look at the pet component on this pet ct,

30:34

we can see a lot of abnormal FDG uptake.

30:37

So again, as we talked about when we talked about the

30:41

gingival buccal area,

30:42

just realize we're gonna run into the same artifacts when

30:46

we're evaluating the oral tongue as well.

30:50

Now here's an example of a patient

30:52

that has a congenital malformation

30:54

involving the oral tongue.

30:55

This is a teratoma.

30:57

So how do we know that this is a teratoma?

30:59

How do we make the diagnosis?

31:01

Well if we see calcifications

31:04

and if we see fat, fat plus calcification equals teratoma.

31:08

And this was an example here of this oral teratoma

31:12

and this arrow right here actually looks at the

31:16

calcification that we're seeing on MR

31:18

that we're actually seeing much easier on ct.

31:21

So this is just an example of an unusual form of a teratoma.

31:27

Now some patients will present with macroglossia.

31:30

So again we can't,

31:31

unless you're actually examine the patients,

31:33

you may not see this,

31:35

but clinically the patients will present with macroglossia.

31:39

Now this is an example of macroglossia that's due to edema.

31:43

This edema can be due to a variety of things.

31:47

Now one thing that I have learned over time,

31:49

if I have someone that comes in with the unexplained edema,

31:54

the first thing in my mind is I wanna make sure they haven't

31:57

had an anaphylactic reaction.

31:59

So it would be a little bit unusual, uh,

32:02

to have an anaphylactic reaction in a patient

32:04

that already has macroglossia.

32:07

So, but on the other hand, if you are doing a CT scan

32:10

and you see edema, the first thing you have

32:12

to make sure they haven't re reacted to the contrast.

32:15

But on the other hand, if I see a patient that's 40

32:18

or 50 years old and I see unexplained edema,

32:21

especially involving the tongue,

32:23

or sometimes I'll see it in the retro pharyngeal space,

32:27

you know, I wanna make sure they don't have calcific

32:29

tendonitis to give the edema involving the

32:31

retropharyngeal space.

32:33

But on the other hand, I also wanna make sure

32:35

that they're not on some type of ace inhibitors.

32:39

'cause remember these ACE inhibitors, one

32:41

of the side effects can be basic, that can be edema.

32:46

So I've, there are a couple of cases

32:48

that we've actually suggested the possibility

32:50

that the edema is due to an ACE inhibitor due

32:52

to the antihypertensive.

32:54

So it's one of these things

32:55

that I would recommend you keep in the back of your mind.

32:59

This is an example of a patient

33:01

that had a large macroglossia

33:03

and this was due to amyloid infiltration.

33:06

And this was an example of macroglossia that was due

33:09

to a large vascular malformation.

33:11

And we could see this is a low flow vascular malformation.

33:15

And this was due to diffuse enhancement

33:17

involving the tongue.

33:20

So when we look at the oral tongue, one

33:22

of the quote unquote pseudo lesions is

33:24

what we're illustrating here.

33:26

So this is a non-contrast T one weighted image.

33:29

So on first glance, when you look at this, you think,

33:32

is there an enhancing mass involving the

33:34

right half of the tongue?

33:35

Well, you always have to check yourself

33:37

and say, well this is a non-contrast T one weighted image.

33:41

Then you have to think yourself,

33:42

is it possible this could be hemorrhage?

33:44

But when you take a closer look, notice

33:46

how this abnormality is basically dead midline.

33:49

It's invasively involving the right half of the tongue

33:53

and it's high signal on T one.

33:55

So this is a nice example of longstanding

33:59

denervation atrophy involving the oral tongue.

34:02

So when you see something like this, what you wanna do is,

34:05

remember as we talked earlier, the motor innervation

34:08

of the tongue comes from the 12th nerve.

34:12

Now this 12th nerve has uh, multiple components to it.

34:16

It eventually passes through the hypoglossal canal right

34:20

below the famous Eagle's beak.

34:22

So if you look at this, we can see the neck of the eagle,

34:24

we can see the head of the eagle and we can see the beak.

34:28

So that's where the 12th nerve passes.

34:30

So if you see something like this,

34:32

you wanna play close attention to the Bai occiput.

34:36

And in this particular case,

34:37

the white arrow shows the normal appearance of the uh,

34:41

eagle's head and the beep.

34:43

And there is a 12th nerve right at the neck.

34:45

And on the right side we can see an aggressive enhancing

34:48

mass that's eroding the Bai occiput

34:52

and involving the 12th nerve.

34:54

So this uh, aggressive mask

34:56

resulted in this 12th nerve policy.

35:01

So the next area that we'll talk about

35:03

is the floor of the mouth.

35:04

Now I'm giving a talk on the oral cavity.

35:07

So I'll use the terminology floor mouth.

35:10

But on the other hand, if I was giving a talk on the spaces,

35:13

I would use the term the sublingual space.

35:17

So pure and simply the sublingual space is that area

35:20

that's below the tongue.

35:22

Now I think Varsha mentioned this in her talk recently is

35:25

that she remembers how I taught her if you,

35:27

the sublingual space is pure

35:29

and simply you stick your tongue out,

35:31

you put your finger under your mouth,

35:33

under your tongue and you press down.

35:35

So everything below your tongue is located

35:38

in the floor of the mouth.

35:39

So when you look at the floor of the mouth,

35:41

the components are the lateral aspect of the mandible.

35:44

And we see this little myeloid line right here.

35:47

There's a muscle that goes in the myeloid line

35:50

to the hyoid bone.

35:51

This is called the mylohyoid muscle.

35:54

That's how it gets its name.

35:56

Now if you look medial to it, we have this gland right here.

35:59

This is the sublingual gland just medial to this.

36:03

We have the submandibular duct.

36:05

This is also known as ton's duct.

36:08

So even though the submandibular gland is down here in the

36:11

submandibular space, we'll see in a couple of slides

36:14

that duct actually crosses into the sublingual

36:18

space below.

36:19

This is a nerve that's the lingual nerve below this on one

36:23

of the many veins involving the floor of the mouth.

36:25

And right below this is gonna be the hypoglossal nerve.

36:29

Then we have a muscle

36:30

that goes in the hyoid bone to the tongue.

36:32

This is the hi gloss muscle

36:34

and just medial to that is the lingual artery.

36:37

So when you look at the sublingual space, we refer

36:40

to this muscle as the myelo hiate sling.

36:44

So when I look at something like this

36:46

and then I see the mandible, that kind

36:48

of looks like a teacup to me.

36:51

So the way that I remember the floor of the mouth is

36:53

that I see the rim of the mandible right here,

36:56

which forms the rim of the teacup.

36:58

The sling right here is the myeloid mylohyoid muscle.

37:02

There's one on both sides.

37:04

So that forms the wall of the teacup

37:06

and then the base of the teacup is formed by the hyoid bone.

37:09

So basically all of these contents that we talked

37:12

to are located in the cup.

37:14

And what would be over the cup?

37:15

Well that would be the tongue.

37:17

So that's how I remember the sublingual space.

37:21

So when we look at the sublingual space,

37:24

the most common tumor

37:25

to involve the sublingual space is going

37:28

to be squamous cell carcinoma of the floor of the mouth.

37:32

So here's an example

37:33

of squamous cell carcinoma of the floor, of the mouth.

37:36

Now how do we know that we're in the sublingual space?

37:38

Well, the way you look at it is

37:40

that you look at these muscles right here.

37:42

These muscles right here are the geno gloss

37:45

and geno hyoid complex.

37:48

At this specific level they go from the genial tubercle back

37:51

to these transverse muscles which are the tongue base.

37:55

So what do you call this?

37:56

That goes from the genial tubercle back to the tongue base.

38:00

Remember lingua is Latin for tongue,

38:02

but glosses is Greek for tongue.

38:05

So when we actually talk about these muscles

38:08

that go from the genial tubercle to the tongue base,

38:11

we use the Greek root and that is genio colossus muscles.

38:15

So the way that we know in the floor we're in the floor

38:18

of the mouth is you look

38:19

for these vertically oriented muscles

38:21

and all of a sudden when they disappear

38:24

and these intrinsic muscles which are more transverse,

38:27

that's how we know we're at the tongue base.

38:29

So this tumor right here is located in the

38:32

left floor of the mouth.

38:35

Now these are other examples

38:37

that can involve the floor of the mouth.

38:39

Again, I'm gonna start with the one on the right.

38:42

Again, components of the floor

38:44

of the mouth are things like muscle,

38:45

they're things like fat, so on and so forth.

38:48

So this was a patient that presented years ago

38:50

with an enlarging tongue

38:52

and this happened to be a lipo sarcoma.

38:55

We can see the large fatty lesion here we can see a

38:58

soft tissue component.

39:00

And again this is a mesenchymal tumor.

39:02

So when you are looking at floor mouth cancers,

39:05

remember any tumor that can involve any of these components

39:08

that we talked about can result in tumors.

39:11

And remember, these components are everywhere in the body.

39:15

Now this is an example of one

39:17

of the weird head and neck ones.

39:18

This happens to be a minor salivary gland tumor.

39:21

Again, in the head

39:22

and neck you can have those minor salivary gland rests.

39:26

But remember in the floor

39:27

of the mouth we actually have the sublingual gland.

39:30

So this can actually be a major salivary gland tumor Y

39:34

because they can actually arise from the sub gland.

39:38

So we have to include minor salivary gland tumors.

39:41

In fact, minor salivary gland tumors are the second most

39:44

likely tumor to involve

39:46

before the mouth behind squamous cell carcinoma Y

39:50

because we have the sublingual gland located

39:53

in the floor of the mouth.

39:56

Now this was another example of a tumor

39:59

that could involve the floor of the mouth.

40:00

So we talked about squamous cell carcinoma,

40:03

we talked about minor salivary gland tumors,

40:05

we talked about mesenchymal tumors,

40:07

but remember when we talked about the floor of the mouth,

40:10

we also talked about nerves.

40:12

So we have to remember nerves also have tumors.

40:16

So how can we suggest the diagnosis that this was due

40:18

to a neurogenic tumor?

40:20

Well remember these nerves are located just medial

40:23

to the mylohyoid muscle

40:25

and then lateral to the genial gloss,

40:27

genio genial hyoid complex

40:29

and just lateral to the mylohyoid muscle.

40:32

So this was a mass right here.

40:34

Well-defined mass that's located in the floor of the mouth.

40:37

When I see something like this again,

40:39

squamous cell is gonna be number one.

40:41

Um, uh, minor salivary gland is gonna be number two.

40:44

But when I see something like this so well defined,

40:48

I'm gonna suggest the possibility of a schwannoma.

40:51

Now I thought this was gonna be a schwannoma,

40:53

but the biopsy came back neuroma.

40:56

I don't know how they got a neuroma.

40:58

Neuromas are typically post-traumatic,

41:00

but I asked a couple of times

41:02

and the pathologist was sure

41:03

that this was a neuroma involving the floor of the mouth.

41:08

Now when we talk about Fluor mouth abnormalities, again,

41:12

remember the SubD gland has this duct that runs in the floor

41:15

of the mouth and eventually it empties out right

41:18

here at the frenulum.

41:19

So in your practice, oftentimes patients present

41:22

with the left sided neck mass, sometimes

41:25

that they're lipomas,

41:26

but sometimes they're actually uh,

41:28

enlarged submandibular gland.

41:31

Remember the insertion

41:32

of the submandibular duct is at the hilum

41:34

of the submandibular gland.

41:36

Then it crosses over the free margin of the mylohyoid muscle

41:40

and inserts at the frenulum.

41:42

And this was an example of a lyth right here

41:45

that a obstructed the submandibular duct

41:48

resulting in an obstructive sil adenitis sitis involving the

41:52

sub gland.

41:54

You can also have abscesses

41:56

involving the floor of the mouth.

41:57

If you have a mass like this,

41:59

remember the odontogenic processes,

42:01

if it erodes the lingual cortex like this

42:04

and extends into the floor of the mouth,

42:06

we can have an abscess involving the floor of the mouth.

42:09

Always remember to look at the bone algorithms

42:12

because if you see this here we see the rotten tooth.

42:15

Here's odontogenic disease.

42:17

This is a little dental caries right here.

42:19

And this was the origin of this left floor mouth abscess.

42:23

So earlier we talked about these infections going laterally

42:27

into the buccal space.

42:28

In this case, if they extend medially, then this is

42:31

how you get a floor mouth abscess.

42:34

If it becomes really bad, we can go on

42:37

to have ludwig's angina.

42:39

This is really a clinical diagnosis first described

42:42

by Wilhem Frederick one Ludwig back

42:44

around the turn of the century.

42:46

And this is an example of ludwig's angina,

42:49

which was all cellulitis.

42:50

This is a choking sensation from an infection,

42:54

but this is an example of what we more typically associate

42:57

with ludwig's angina.

42:59

Multiple abscesses extending along the compartments

43:02

of the floor of the mouth, essentially resulting in

43:04

compartment syndrome.

43:06

This can extend into the airway,

43:08

it can give you laryngeal edema

43:10

and this gives you the strangulation.

43:12

And these are patients

43:13

that had ludwig's angina due to cellulitis.

43:16

This would have the abscess

43:18

and this patient had to have all of these abscesses drained.

43:22

You can also have developmental lesions involving the floor

43:25

of the mouth if it's anterior

43:27

and midline, these are epidermoids.

43:30

So here it is, high fluid collection,

43:33

high signal on T two and on ct.

43:35

This is due to small little areas

43:37

of ectopic derm getting caught in the midline plates.

43:42

Your mouth develops.

43:43

And on the other hand, if you have a cystic lesion involving

43:47

the lateral aspect of the floor of the mouth

43:49

that is contiguous with the subretinal gland, then we have

43:53

to think of a frog and we have to think of ulus.

43:57

So this is an example, another example of a granula.

44:00

They're paraline, they're fluid collection

44:03

and they're felt to be uh, some type of obstruction

44:05

or malformation.

44:07

Some people even say mucus seal, I don't like that term,

44:10

but some people will use that of the sublingual gland.

44:13

If they can extend inferiorly through the mylohyoid muscle.

44:17

Oftentimes there's a little defect in

44:19

the floor of the mouth.

44:20

Notice in normal mylohyoid muscle on the right,

44:23

there's a defect on the left.

44:24

And if there is a defect, these ulus can extend inferiorly

44:29

through the submandibular space through

44:31

what we call a ER deformity.

44:34

And this is what's referred to as a complex ula.

44:37

So if it's in the floor of the mouth,

44:38

it's simple if you will,

44:41

but if it extends into the submandibular space

44:43

through a defect, we can call this either a diving

44:47

of plunging or a complex ula.

44:50

Another example here, this was an example

44:53

of a floor mouth arteriovenous malformation.

44:56

These oftentimes I've seen 'em arise in younger women,

44:59

especially in pregnancy

45:01

because they either the hormonal changes

45:03

the higher blood volume.

45:04

Both of these patients were in younger patients

45:07

that were both pregnant,

45:08

and oftentimes they'll actually present with rapid bleeding

45:11

because of that bl blood volume.

45:14

So oftentimes they'll be quiescent.

45:16

But when you do have these changes, all

45:19

of a sudden they can present with rapid bleeding.

45:23

Well the last two areas that we'll talk about are first

45:26

of all gonna be the retromolar trigone.

45:29

So what is the retromolar trigone?

45:31

Well, the retromolar trigone is that area that's

45:34

behind the last molar.

45:35

So you have the central incisor, lateral incisor,

45:38

canine first, premolar second premolar, first molar,

45:42

second molar, third molar.

45:43

And this triangular space behind the third molars referred

45:47

to as a retromolar trigone.

45:49

Now for those of you that have had your wisdom teeth

45:52

resected, congratulations,

45:54

you have the largest retromolar trigones on this seminar.

45:57

So you are the best at something I know I've always wanted

46:00

to be the best at something, I've never quite accomplished

46:02

that, but I still have my wisdom teeth.

46:04

So I didn't make the cut on this,

46:06

but if you look, we talked about this earlier,

46:09

here is the buccinator muscle.

46:11

Here's the superior constrictor muscle.

46:13

And right here is the tego mandibular.

46:16

So the implied anatomy behind the retromolar trigone is

46:20

that this tego mandibular Raf is here.

46:23

And on the sagal images from Elsevier,

46:26

we can see this location of the retromolar trigone.

46:29

The other applied anatomy is the proximity

46:32

of the anterior portion of the mandible

46:34

to the retromolar trigone.

46:36

This complex anatomy is super important

46:39

for retromolar trigone.

46:41

So first of all, there's an example here

46:43

of a retromolar trigone carcinoma.

46:46

They can extend laterally, they can extend posteriorly

46:50

anteriorly and directly uh, posterior laterally.

46:54

So the point about retromolar trigone carcinomas is

46:57

that if you take a four centimeter tumor

46:59

and you stick it in the oral tongue,

47:02

well it's just gonna grow in the tongue.

47:04

But on the other hand, if you stick a four centimeter tumor

47:07

here, it can extend anteriorly posteriorly,

47:10

it can extend anteriorly here in a row, the back

47:14

of the mandible, and it can extend posteriorly in a row,

47:17

the anterior cortex of the mandible.

47:20

These are really, really important spread patterns

47:23

that you just can't see clinically.

47:24

We had a patient yesterday that had a retromolar trigone

47:28

and the surgeons had no idea that had eroded the bone

47:31

or extended anteriorly.

47:33

So this is where we really, really make a difference.

47:36

So here's an example of a retromolar trigone carcinoma.

47:40

Now I put a little tiger here.

47:41

I'm from Bengal, India

47:42

and these are my famous tiger stripes.

47:44

I love my tiger stripes.

47:46

So if I draw a line down the middle, compare the right side

47:49

to the left side, what I see here is I see mucosa right here

47:54

involving the lip, then I see fat,

47:56

then I see again gray right here,

47:59

which is the outer portion of the lip.

48:00

And then I see fat. So these are my normal tiger stripes.

48:04

But on the right hand side,

48:05

notice my tiger stripes are gone.

48:07

And what I see is this large mass that has a semi,

48:11

a comma shaped appearance involving the retromolar trigone.

48:14

So that's the full extent of this.

48:17

Now, because these tumors can grow superior along the tego

48:21

mandibular ra, it's always important to look all the way up

48:25

to the hook of the ulus.

48:26

So here's a tego man, and here's the hook of the ulus.

48:30

So on the left hand side, here's the look hook of the ulus.

48:33

And here are my normal tiger stripes.

48:35

See the black, see the gray right here?

48:37

See this right here on the opposite side?

48:40

Here's the hook of the ulus. And notice my stripes are gone.

48:44

This is all blurry.

48:45

This is very subtle superior extension

48:48

of this retromolar trigone carcinoma all the way up

48:51

to the hook of the ulus.

48:53

And the reason why I emphasize this so much is that

48:57

I think part of the reason these tumors do so poorly is

49:01

that they're under staged

49:02

and underappreciate on clinical examination.

49:05

Another example here, here's a retromolar trigone carcinoma.

49:09

Clinically they thought they could get this out,

49:12

but on the other hand, if you look closely,

49:14

there's actually bone erosion here involved in the anterior

49:17

aspect of the mandible.

49:18

That was not the detected on clinical imaging.

49:21

Rather, the surgeons looked in the mouth

49:22

and they saw this component,

49:24

but they didn't appreciate this deep opponent.

49:26

And again, look at my tiger stripes, see

49:28

how the tiger stripes are obliterated.

49:31

And one more example, this was a patient

49:34

that the surgeon thought

49:36

that they could get out doing a partial mandibular me,

49:40

but on the preoperative imaging,

49:41

what they didn't appreciate was the replacement

49:44

of the signal within the mandible.

49:46

And when we gave contrast, all

49:48

of this was enhancing right here.

49:50

So the surgeons ended up doing a partial mandibular,

49:53

they didn't get enough and came back with a positive margin.

49:56

So I strongly recommend retro retromolar trigone carcinomas

50:00

to undergo CT and contrast enhanced MR

50:04

because the CT is gonna be better

50:06

for the vertical early cortical innovation.

50:09

But the MR is gonna be better to look

50:11

for all the involvement of the marrow.

50:13

So it truly is complimentary.

50:17

So the last couple things about the retromolar trigone is

50:20

that you can have infections involve the retromolar trigone

50:24

and they're typically from, again, odontogenic infections

50:27

involving the alveolar ridge.

50:30

So if you have a maxillary uh molar tooth

50:32

that becomes infected,

50:34

you could end up having a little abscess here.

50:36

And again, compare my tiger stripes.

50:38

Look at the left side, see the nice stripes right here.

50:41

Again, there's the abscess right here.

50:43

Another example here, this is not abscess,

50:46

but a big flagon involving the medial rectus muscle.

50:49

Notice, excuse me, the medial oid muscle.

50:51

Notice the medial oid muscle on the left.

50:54

Notice how it's all inflamed on, right?

50:56

Again, this was all due to odontogenic disease.

51:00

If the infection extends laterally, you can end up having

51:04

myositis involving the masseter muscles.

51:06

Again, this was a wisdom tooth that was resected.

51:09

Unfortunately, the patient developed an infection

51:11

and developed bilateral uh,

51:14

myositis involving the mass of the muscles.

51:16

Again, all due

51:17

to odontogenic infections in the retromolar trigone.

51:21

And this was an example of medication related osteonecrosis.

51:26

If we look at the bone right here, we can see the bone

51:28

and bone appearance.

51:30

You could see this following radiation therapy.

51:32

But if you have patients that somehow have jaw pain,

51:35

especially in elderly females that are on some type

51:38

of calcium replacement medications,

51:41

always consider the possibility

51:43

of medication related osteo necrosis.

51:47

And the last thing that we'll talk about is the hard palate.

51:51

So when we talk about the hard palate, it's very,

51:53

very interesting because it has numerous components to it

51:56

and a lot of important applied anatomy.

52:00

So when we look at the palate,

52:02

we have these two plates right here,

52:04

which are the pallo process of the maxilla.

52:07

Then when we look more posteriorly,

52:09

we have the flattened component here of the palatine bone.

52:13

Remember the palate has its own bone,

52:15

it's actually shaped as an L.

52:17

It has a vertical component which would basically

52:20

go into the screen.

52:21

But this flat component right here forms that hard palette.

52:26

It also has a few foramen.

52:28

We have the incisive frame

52:29

and here we have this little frame

52:31

and which is the greater palatine frame.

52:33

And then we have a lesser palatine frame

52:35

and which is located here.

52:38

So this is just an example of a large incisive canal cyst.

52:42

I saw this case about probably about two months ago.

52:44

This patient presented with really bad breath apparently.

52:47

So this would have intermittent drainage.

52:50

And when we looked at this, this was the largest incisive

52:53

canal cyst I'd ever seen.

52:54

We can actually see it here pooching into the inferior

52:57

portion of the nasal cavity.

52:59

And we can see the submucosal mass here.

53:02

It presented with the heart palate,

53:04

but this was all due to an incisive canal cyst.

53:08

Now the most common tumor

53:09

to involve the hard palate is going

53:11

to be squamous cell carcinoma.

53:13

Again, squamous cell carcinoma is gonna be number one.

53:16

And in general you can look right in there

53:19

and see that big squamous cell carcinoma.

53:22

But remember we talked about that applied anatomy.

53:25

So if I go back to this slide, we can have these greater

53:28

and lesser palatine frame

53:29

and these squamous cell carcinomas can extend posteriorly.

53:33

Here's the normal greater palatine frame.

53:36

And on the left, and notice the palatine frame.

53:38

And on the right is enlarged, eroded, and expanded.

53:42

And this is actually retrograde perineural spread

53:45

of squamous cell carcinoma.

53:48

When we are evaluating these tumors,

53:50

we also wanna look at the bone

53:52

because if this tumor is just limited to the mucosa,

53:55

then they can do a wide local excision.

53:58

But if we say there's potential peroneal spread

54:01

or if there is bone erosion such as this,

54:04

then the patients have to end up going some type

54:06

of maxillectomy.

54:08

And I can tell you yesterday in clinic,

54:10

again it was a crazy day in clinic, we had a patient

54:12

that came in with a minor salivary gland tumor

54:15

that they thought was a superficial lesion,

54:17

but there actually was perineural spread along

54:20

that greater foramen.

54:21

So I haven't gotten the slides yet,

54:23

but the next time I give this I'll be sure to show it

54:26

because it was kind of a crazy case.

54:29

So number one is gonna be squamous cell carcinoma.

54:32

The second one is gonna be minor salivary gland tumors.

54:35

When we look at the hard palate,

54:37

there is again a higher density

54:39

or proportions of minor salivary gland tissue

54:43

in the hard palate.

54:44

So this has a propensity for the hard palate,

54:47

the soft palate, the buccal space, and also the tongue base.

54:51

So when we are looking at tumors involving the hard palate,

54:54

number one is squamous cell carcinoma,

54:56

and number two are gonna be minor salivary gland tumors.

55:00

How can we tell the difference?

55:02

Well, it's really, really hard to tell.

55:04

I think if we see something that has high T two signal

55:07

and is well-defined, we can suggest

55:10

that it's a benign lesion like a pleomorphic adenoma.

55:13

But again, it's really up to pathology.

55:16

When we see something like this, then we have

55:19

to consider squamous cell carcinoma

55:21

or muco epidermoid carcinoma.

55:23

And again, if you look real closely,

55:25

notice this enlargement right here

55:27

of the greater palatine frame

55:29

and on the left compared to the one on the right.

55:31

So again, anytime that you see these tumors extending

55:34

laterally, we have to take a close look

55:37

to make sure we don't have that perineural invasion

55:40

'cause that makes all the difference in the world.

55:44

And the last thing that I'll end on is

55:46

that once these tumors end up growing along the greater

55:49

or lesser palatine nerve,

55:51

they can go here into my favorite foramen.

55:55

So this foramen is located between the OID plates

55:59

and the palatine bone, and that's the tego palatine fossa.

56:04

So this is an example of a tumor

56:06

that's located in the left tego palatine fossa.

56:10

So the normal anatomy here is S phenyl, palatine foramen,

56:14

tego palatine fossa.

56:15

Once they get into this fossa, they can jump on V two.

56:19

This is the second division of the fifth cranial nerve.

56:22

Here we see on the coronal images we could see abnormal

56:25

enhancement of V two.

56:27

On the left, on the right side,

56:29

you can actually see the nerve surrounded

56:31

by the vascular plexus.

56:32

And if you have a really sharp eye,

56:35

you can actually see abnormal enhancement involving VNS

56:38

nerve on the left compared to the right.

56:40

See that right there? There it is right there.

56:43

And on the axial images, we can actually see the tumor.

56:46

So the reason why this is important is

56:48

that these tumors can jump on V two

56:51

and go all the way back into Mecca's cave.

56:54

So here's Mecca's Cave on the right hand side,

56:56

the normal appearance, and here it is on the left.

56:59

So when you see something like this,

57:02

this has made all the difference in the world over the last

57:04

30 years when I was most of your old's age,

57:07

'cause I assume all of you are younger than me.

57:09

Our referring physicians didn't believe that we

57:12

as radiologists could actually identify peroneal spread

57:16

and we would tell 'em, but they would go in and operate.

57:19

Now, if we

57:20

as a radiologist say there's actually perineural

57:23

spread, they listen to us.

57:24

And in fact, if we say there's perineural spread back into

57:28

Mecca's cave, especially in patients

57:30

with squamous cell carcinomas

57:32

or minor salivary gland tumors in involving the palate

57:35

or the maxilla sinus,

57:38

oftentimes these patients are gonna be treated

57:41

with non-surgical organ preservation therapy and,

57:44

and not be treated with surgeries.

57:46

So one of the joys that I have in head

57:48

and neck radiology is I've seen a complete transition over

57:51

the last 30 years and it just emphasizes

57:55

to me the important role

57:56

that we play in taking care of our patients.

57:59

So in summary, what we did over the last 55 minutes

58:02

or so is that we talked about the different subsites

58:05

of the oral cavity.

58:07

I tried to give you a differential diagnosis

58:10

of the most common things

58:11

that you'll see in each one of these sites.

58:14

And my hope is, is that over time you'll really appreciate

58:17

to learn the anatomy, the head and neck.

58:20

And for me, you know, I can't think

58:22

of another job I'd rather do than

58:24

to be a head and neck radiologist.

58:25

So thank you very much for your attention

58:28

and I'm happy to answer any questions. Thank

58:31

You so much for that Awesome lecture Dr.

58:33

McCury. Yeah,

58:34

at this time we're gonna open up the floor to questions.

58:36

So if you've got those, put those into that q

58:38

and a feature so we can get through as many as we can.

58:43

And I'm not sure if you can open up that box,

58:45

the q and a box, Dr. McCury, are

58:47

We doing chat or are we doing uh,

58:49

Uh, go questions?

58:51

Yeah, the q and a, uh, bubble, that box, if you pop

58:55

that open, you got a bunch

58:57

Of, I see the webinar chat.

58:59

I don't see the key. Where's the q and A chat? Let's see.

59:02

Okay. It might be, Did you speak the chat?

59:05

Um, they're coming through the, um, the bubble.

59:08

If you wanna hover your mouse on the

59:11

top of your screen, you might see it. I got

59:13

It now. I think I got it.

59:14

I got webinar chat. Okay, great. Okay.

59:18

Alright. You want me to start at the top?

59:21

Yeah. Perfect. Okay, great. Okay.

59:24

Um, let's see.

59:27

I'm gonna go down there without jumping over the questions.

59:30

So, um, so the radiological features of the hard palette.

59:34

Um, so I just like, I confuse you there,

59:37

so I don't want to confuse you there.

59:38

So the hard palette on the sagal images,

59:42

this is gonna be the hard palette that's located here.

59:45

So when we talk about the hard palate, it's probably one

59:49

of the most easier areas to see

59:52

because this is the sagal image right here

59:54

looking at the hard palate.

59:56

The hard palate has really two primary components to it.

60:00

Like I mentioned before, we have these, uh, uh,

60:04

palatine processes of the maxillary bone.

60:07

And then we have this portion right here,

60:09

which is the vertical or the horizontal plate of the palate.

60:14

So these are all the components of the hard palate.

60:17

We have the incisive canal here and the greater

60:19

and the lesser palatine frame it.

60:22

So when we look at the axial image, here's the hard palate

60:25

that's located here.

60:26

And then on the sagal images, this is the hard palate

60:30

and this just happens to have a tumor

60:31

that's eroding the hard palate.

60:34

So hopefully I answered, uh,

60:36

hopefully I answered that question.

60:39

Yeah. Dr. McCury, I'm gonna read you,

60:41

we've got a bunch in the q and a box, so I'll go ahead

60:44

and read those out to you and then

60:45

we can pop over to the chat.

60:47

Okay. There's you do your thing.

60:49

I'll just tell you each, I'll just answer what you,

60:51

to me. Okay. Awesome.

60:53

Okay. Um, what SEL views can we use

60:57

to see better the oral tongue

60:59

and calculate the depth of invasion?

61:02

Um, so again, you're sort

61:04

of talking about the depth of invasion.

61:06

Um, I'm gonna plead, uh,

61:09

at this point in time, try not to do that.

61:12

I'm gonna, I'm gonna suggest that if you want

61:15

to measure the tumor thickness, um, then

61:19

what I would suggest doing is to, um, look at

61:24

whatever orthogonal view will give you the best location

61:29

to go from the surface to the depth.

61:31

Like I said, I do not measure the,

61:34

the lateral thickness at all, um, uh,

61:38

unless they ask me to.

61:39

What I do mention, so for instance,

61:41

I dunno if you can see my screen here, Ashley,

61:43

can you see the screen right here?

61:44

Yeah. So what I do here is

61:46

that I will measure the largest measurement that I can get

61:49

because that factor specifically into the A JCC.

61:53

But when I talk about this thickness right here,

61:55

I would go from my arrow here to out here

61:58

and just say that if they want to, I'll just say this,

62:01

tumor thickness is about what, a centimeter

62:03

and a half or two centimeters.

62:05

But the main thing is whether or not it crosses midline

62:08

because in the situation like this,

62:11

oral tongue cancers are likely gonna be non HPV positive.

62:15

So for instance, in the image here on the middle image,

62:19

I would go ahead and mention this cross-sectional thickness,

62:22

but what they really want

62:23

to know is what's the relationship to midline.

62:25

So you can comment on tumor thickness if you want to,

62:28

but from a macroscopic perspective,

62:31

because it's not HPV positive,

62:33

these are usually HPV negative,

62:36

they're usually treated with surgery.

62:39

The margin has to be about a centimeter oncologic

62:42

margin of a centimeter.

62:44

So what's really important, at least from from my um,

62:47

experience, is how close does this tumor get to the midline?

62:50

And also how deep does the tumor get?

62:54

So in this particular case, the wideness here goes

62:58

to right about the midline.

63:00

So in order to get the oncologic margin,

63:02

they'll have to come here.

63:04

But more importantly, it's not necessarily trying

63:06

to guess the depth of invasion,

63:08

but look how inferiorly this tumor gets.

63:10

Look at my tiger stripes on the left hand side.

63:13

See all of this area right here?

63:15

This is the most important thing

63:17

because oftentimes surgeon underestimate that inferior depth

63:21

and if they don't get it all the way down here,

63:24

they're gonna end up having a positive margin.

63:26

And for me, that's the most important thing

63:28

to measure when you're looking at tumors.

63:31

It's not necessarily the depth of invasion,

63:33

but macroscopically, what does a surgeon have to resect

63:37

in order to get a gross tumor resection

63:40

and have negative margins?

63:43

Sorry for the long reply.

63:45

No, that was great. You actually

63:46

had a couple questions on that.

63:47

So, um, uh, yeah, you answered a couple at once.

63:52

Uh, for our next one, how do you differentiate

63:54

between vascular tumor like human geno, gen, excuse me,

63:58

or veo phatic malformation involving the

64:01

subular gland, which is more common?

64:05

Yeah, so that's a great question, honestly.

64:07

Um, that's a talk to itself.

64:09

I have a 45 minute talk on, um,

64:13

a simplified approach to vascular malformation.

64:16

So if you guys ever want me to give

64:18

that Ashley, I can give it to you.

64:20

Um, what I can say really briefly is that there's a lot

64:24

of confusion about the nomenclature.

64:27

He angios are distinct entities from vascular malformations.

64:32

He angios are characterized by endothelial proliferation

64:35

that can be hypervascular

64:37

and they're oftentimes associated

64:40

with a surrounding soft tissue mass.

64:43

A venal lymphatic malformation is a,

64:47

does not have endothelial proliferation.

64:51

And the ov lymphatic malformations

64:54

typically involve a muscle.

64:56

Um, they typically have fallates

65:00

and they do not have the flow voids

65:02

that we see in the proliferative phase of a he angio.

65:05

So they do not have a necessarily a

65:08

surrounding soft tissue mass.

65:09

Rather, they oftentimes have, uh, uh,

65:12

fluid containing structures that are more characteristic

65:16

of a, a fetal lymphatic malformation.

65:18

So I really can't get into that too much more.

65:21

Uh, but I can give a future talk on that if, if you want.

65:25

Yeah, for sure. Okay.

65:29

Um, can the marrow be infiltrated

65:31

with in evident cortical destruction on ct?

65:36

Uh, yes, it can be.

65:37

Um, so I think a lot of it depends on your technique.

65:41

I would say that the likelihood of having

65:45

tumor involving the marrow without

65:49

cortical erosion on a very,

65:52

very good quality CT is very rare.

65:55

But if you are looking at your, um,

65:59

assessing your CT scans with thick sections

66:03

and bone windows, then there's a high likelihood that your

66:07

resolution on your CT scan may not be sufficient to look for

66:11

that cortical erosion.

66:13

I would say that if you have a, a very, very thin section CT

66:18

and the cortex is intact

66:19

and the likelihood that you have tumor

66:21

in the marrow is rare.

66:22

Now, having said that, um, you can have,

66:27

and I have seen this

66:28

before, is that you can have a completely intact cortex,

66:33

but the marrow is replaced.

66:35

Now all squamous cell carcinomas have a very robust

66:40

peritumoral inflammation.

66:42

So when you look at the marrow, sometimes

66:44

what ends up happening is that you have marrow replacement

66:47

and that's all inflammation.

66:50

And then the question comes up is that inflammation just,

66:54

uh, benign inflammation or is a tumor?

66:58

And we really can't tell, I can give you my impression is

67:03

that if I look at A-G-B-M-A brain GBM

67:06

and I see vasogenic edema, it's been shown that

67:09

that vasogenic edema contains choline.

67:13

So, which means there are tumor cells surrounding in

67:16

that edema surrounding the brain tumors.

67:18

So my opinion is that if I have a reasonably sized

67:24

carcinoma that's adjacent to the bone

67:27

and I see replacement of the marrow, you know,

67:31

I am concerned that even if it is inflammation,

67:35

I'm concerned that there is microscopic disease

67:38

within that inflammation.

67:39

And that's just my, uh, that's just my opinion.

67:42

Um, and I always convey that, uh,

67:44

to our surgeons in general, if I say the marrow's replaced,

67:48

um, then they're probably gonna do an extended ectomy

67:54

Awesome explanation.

67:56

Um, uh, there's a clarification question.

67:59

Did you say perineural spread

68:01

and perineural invasion are not the same?

68:05

That's correct. Perineural invasion, in fact,

68:07

I think you can see my slide, right?

68:10

Yes. Yeah.

68:11

Perineural invasion is a microscopic diagnosis

68:15

where the pathologist looks at the tumor

68:18

and sees small little nerve nerve fibers

68:23

that are completely invaded

68:25

or involved with tumor perineural spread.

68:29

And I'll see if I can get to get to this.

68:33

Perineural spread is a macroscopic diagnosis where,

68:37

uh, can you see my screen, Ashley?

68:39

We can actually see the tumor itself that is involving

68:44

and enhancing the nerve and oftentimes enlarging it.

68:47

So perineural invasion

68:49

and perineural spread are two distinct entities.

68:54

And any tips for evaluating perineural spread?

68:59

Yeah, so Mr. Right here.

69:00

So what you wanna do in order

69:02

to evaluate perineural spread is

69:04

that you wanna do thin section images, uh,

69:06

you wanna give contrast

69:08

and uh, what you do is you look for abnormal enhancement.

69:12

And oftentimes when it's more advanced, you can see

69:15

involvement of the nerve.

69:17

So for instance, when I look at this image right here,

69:20

here's the normal nerve right here

69:22

and there's the vascular plexus.

69:25

This is the same nerve on the opposite side.

69:27

And notice how there's abnormal enhancement

69:29

and enlargement of that nerve going through.

69:32

In this case it happens to be raben rotundo.

69:38

Okay, gotcha. Why is it

69:43

important to distinguish between primary tumor

69:45

of the lip from those of buccal mucosa

69:49

Of the buccal mucosa?

69:50

Mm-Hmm. So, um, yeah, so that's a good question.

69:55

So it, it, I mean, it is really hard on imaging

69:58

to separate out a, a lip cancer.

70:01

Lemme put it this way, a lip cancer just involves a lip.

70:04

The buccal mucosa is when the tumor creeps on

70:08

the backside of the lip

70:10

and actually starts extending into the oral cavity.

70:14

So if it's, if it's on the outside of the lip

70:16

and there's no deep extension,

70:18

then the surgeons can potentially just chop it off

70:20

or do a small little skin graft.

70:23

But once it actually extends on the back surface of the lip,

70:26

then oftentimes the surgeons are gonna have to take

70:28

that whole lip out.

70:30

But in general, from an imaging standpoint,

70:33

it really is hard to determine

70:36

the full extent of lip lesions.

70:38

The most important thing is to try to identify whether

70:41

that tumor that's involved in a lip extends deeply into the

70:45

gingival buccal sulcus.

70:47

And also whether it involves the gingiva overline,

70:51

the mandible in the maxilla, that's

70:53

what we can do on imaging if we do

70:55

that puff cheek technique.

70:56

But remember, that area can also be seen, um,

70:59

on clinical examination as well.

71:01

So we wanna make sure there's no large submucosal

71:04

extension of the tumor.

71:08

Gotcha. Do you recommend a specific time of acquisition

71:11

after contrast for detection of head and neck cancers?

71:16

Yeah, we do. Um, what I like to do is,

71:19

I'll give you a historic perspective.

71:21

Um, in the old days, we would just give contrast

71:25

and then we would acquire the images.

71:27

But then what ended up happening is that

71:29

with multi detector ct, if you give the contrast

71:33

and just image, basically everyone's getting a CT

71:35

angiography because we're imaging so fast.

71:38

So the purpose, I'll leave it this way, is the purpose

71:41

of giving contrast is twofold.

71:44

Number one is that you wanna make sure

71:47

that you have a opacification of the vessels,

71:50

and that's both the arteries and the veins

71:53

because you wanna make sure that, you don't want

71:57

to call it un opacified vein a lymph node.

71:59

So you wanna make sure lymph nodes

72:01

and vessels are completely separate

72:03

and you can see the vessels

72:05

and separate those from the lymph nodes.

72:06

So that's number one. The second thing is, is

72:09

that if there is enhancement of tumors,

72:13

if you do have a tumor, tumors can enhance.

72:15

Now tumors enhance differently,

72:18

but what you wanna do is when you give contrast,

72:21

you wanna give sufficient time such

72:24

that the contrast material has enough time to

72:27

permeate into hypervascular tumors, any type of tumor.

72:32

So the best way that we like to do is that

72:36

after multi detector CT came out,

72:38

we published this I think probably about 15 years ago,

72:40

20 years ago, is that we give, if you will, a loading dose

72:44

of about 50 ccs

72:48

and we wait 90 seconds.

72:50

So we wait 90 seconds.

72:52

And that gives enough time for the contrast to cycle

72:56

through if you the arterial to venous phase

72:59

and also gives it enough time for the contrast to,

73:02

to go into tumors.

73:03

And then what we do is we give another 25 to 50 ccs

73:08

and then we image again.

73:10

And that 25 to 50 ccs just ensures

73:14

that the contrast is actually in that vascular phase again.

73:17

So the first half of that loading dose, if you will, is

73:20

to make sure contrast is enough time to get into tumors,

73:23

and the second half is to opacify the vessels.

73:26

And then a lot of this is just fine tuning on your end.

73:29

What you wanna do is have equivalent

73:31

of ification of the, of the vessel.

73:33

So you know, when you give that second dose,

73:36

you may give more, you may give less,

73:37

you may have a little bit of a delay,

73:39

but that, that's something that you can kind

73:40

of tweak in your own practice.

73:44

Okay. We'll do a couple more here.

73:47

Um, this is, this is kind of random,

73:49

but, um, do you have a, a book you would suggest

73:53

for a dental student for radiology?

73:59

That's a great question. Um, you, um,

74:02

I, that's a good question.

74:03

I, I think, um, I mean there's

74:05

so many books that are written out.

74:06

I think you're probably looking for something

74:08

that's super concise to get you there.

74:11

Um, I'd have to think about that.

74:15

I think the books by Elsevier, uh, are really good.

74:18

Uh, the, they have terrific pictures in 'em, which I think

74:22

you'll find really, really helpful.

74:24

Um, they're, they're a little bit hard to read and sense.

74:26

There's a ton of words in them.

74:27

So I, I think it, it take a little bit while,

74:30

but the images are great.

74:31

So if you're a visual person, I think

74:33

that would really be helpful.

74:35

Um, otherwise, uh, you know, there are various, uh,

74:39

for instance, I'm gonna, uh, just, you know,

74:42

I think you mentioned that I'm a, uh, uh,

74:43

editor in chief for the clinics.

74:46

So for instance, like in the clinics,

74:48

we do have short little concise

74:50

monographs on various topics in all of neuroradiology.

74:54

And we've done several on the head and neck.

74:56

So if you want something that's concise, clear

74:59

and concise, that's focused on a certain topic,

75:01

I think those are helpful too.

75:03

Um, also, um, you know,

75:05

if you have specific questions you can do

75:07

what I end up doing a lot was googling stuff and try to,

75:09

and try to find out,

75:10

but I don't know if there's like a, uh, you know, one, 100

75:14

or 200 page book that's gonna give you everything you need.

75:17

The other book that's good too is The

75:19

Requisites by Dave uim.

75:20

I think that's a really good book too.

75:21

Um, I think that's both neuro and head and neck,

75:25

but I think that head and neck section, uh,

75:27

would be a good start as well too.

75:28

So those are three or four options for you.

75:31

Awesome. All right.

75:33

Um, we'll do this one

75:36

and then call it, how do you differentiate

75:39

between osteonecrosis

75:41

of mandible post radiotherapy versus osteomyelitis?

75:45

Yeah, that's a great question.

75:46

Um, so the, there are a couple things.

75:50

Um, number one, again, I'm biased

75:54

because I see patients.

75:56

So when I go and see the patients, um,

75:59

osteo radionecrosis is actually dramatic to see

76:03

because depending on

76:06

how advanced the osteo radionecrosis is,

76:08

you walk in the room, you can literally see the bone

76:12

sticking out and when the patients can literally spit,

76:15

they can actually take their finger

76:16

and either spit it out, the surgeons can go in

76:19

and take the pliers

76:20

and take some of the bone out of the mandible.

76:22

It's pretty dramatic.

76:24

Now, in full frank osteomyelitis, you could have

76:27

that aggressive bone erosion and the destruction,

76:31

but oftentimes there's a lot

76:32

of soft tissue components surrounding it.

76:35

So for instance, when I showed that case of the medication,

76:38

um, related osteonecrosis notice,

76:42

I specifically chose this case

76:44

because there was some soft tissue

76:46

that I think you can see my screen right, Ashlyn, um,

76:50

you can see that the, is that right ash?

76:52

Yep. Can see it. Okay.

76:53

So you can see that the mass muscles a little bit enlarge,

76:56

but notice the fat right here, the fat's very clean.

76:59

If this was a rip roaring osteomyelitis,

77:01

you would see inflammation

77:03

and edema surrounding the soft tissues.

77:06

So, uh, radiographically, this could be either

77:09

or if I just looked at this,

77:10

but the fact that this fat is so clean that suggests

77:13

that this is more osteonecrosis as opposed to osteomyelitis.

77:18

Now having said that, clinically, if they have a patient

77:21

that does have osteonecrosis, that's radiation associated

77:25

and it's progressive, they'll go ahead

77:27

and put the patient on antibiotics.

77:31

Because oftentimes in the radiology we like to say either

77:34

or, but in the real world,

77:36

you can have two things happening at a time.

77:39

So in the real world, if you see something like this,

77:41

they'll go ahead and put the patient on antibiotics in hopes

77:44

that if there is an overlying infection

77:47

that could be exacerbating this,

77:49

they'll try to clean it down.

77:53

Super helpful. Thank you so much.

77:55

I think we'll end it there. Thank you

77:58

for answering all those questions

77:59

and for your amazing lecture.

78:01

We're doing part two on November 14th,

78:05

the Anatomy and Pathology of the Ora Phix.

78:09

Did I say that right? Dr. McCury

78:10

Ora phn. Yeah. You're getting there

78:11

Ashley. I'm

78:12

Become, I'm a radiologist in training.

78:15

You're a head and neck radiologist in training.

78:18

Well, thank you again for being here. That was excellent.

78:21

We really appreciate it. And for everyone else, thank you

78:23

so much for signing on and asking such amazing questions.

78:26

We hope we see you November 14th

78:28

for part two of this lecture.

78:30

Be on the lookout for registration info on that.

78:35

Alright, thanks everyone for attending.

78:37

Ashley and the team, thanks so much

78:38

and thanks everyone for taking the time to participate.

78:42

Absolutely. Thank you. And, and everyone be else.

78:45

Be sure to join us next week on Thursday,

78:47

October 3rd at 12:00 PM Eastern, Dr.

78:50

Singal will deliver a lecture entitled

78:52

Ultrasound of the Bowel.

78:53

You can register for that@mriline.com

78:56

and follow us on social media

78:57

for updates on future NOOM conferences.

78:59

Thanks again for learning with us and have a great day.