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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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0:30

Today we are honored to welcome Dr. David Ssim

0:32

for a case review entitled Sal Nasal Case Review,

0:35

vitamin C and D.

0:38

Dr. Ssim is a neuroradiologist

0:40

and professor of radiology at the Johns Hopkins

0:42

University School of Medicine.

0:44

He's the author of more than 350 scientific papers

0:47

and several popular books in radiology,

0:49

including Neuroradiology the Requisites,

0:52

and is a series editor of the case review series.

0:55

He has served as the president of A SNR

0:57

and was awarded the Outstanding Educator

0:59

Award from the RSNA.

1:01

We are grateful to Dr.

1:02

Usin for her support of MRI online

1:04

and for serving as our neuroimaging subspecialty advisor

1:08

at the end of the case review.

1:09

Please join him in a q

1:10

and a session where he'll address questions you may have on

1:12

today's topic and please remember to use that q

1:15

and a feature to submit your questions so we can get to

1:17

as many as we can before our time is up.

1:20

With that, we're ready to begin today's case review. Dr.

1:23

sso, take it from here.

1:25

Thank you very much.

1:28

So today we are going to go

1:30

through some multiple choice questions on Cy Nasal

1:33

Imaging Unknown cases.

1:35

I'd like to have as much participation

1:38

as I can from the standpoint of the polling

1:40

and the multiple choice answers and we'll see how you do.

1:46

So let's, uh, get going.

1:47

Just as a reminder, my mnemonic vitamin C

1:51

and D refers to vascular, infectious, traumatic,

1:54

acquired metabolic idiopathic neoplastic

1:57

congenital and drugs.

1:58

And those are the general categories of disease

2:01

that we see across the full spectrum of pathology in the

2:06

body and in the Cy nasal cavity, obviously it's going

2:08

to be dominated by infectious etiologies,

2:11

inflammatory etiologies and neoplastic etiologies.

2:15

So let's begin.

2:18

And um, my disclosures, I do have several books, um,

2:21

published by Elsevier for which I receive royalties.

2:24

I do medical-legal expert witness work,

2:26

and I am, uh, one of the consultants

2:27

and speakers for MRI online or modality.

2:31

And yes, the fifth edition of nerve radiology,

2:34

the core requisites is coming out in March.

2:36

So, uh, go to the Elsevier site

2:39

or um, Amazon, wherever you want.

2:41

All right, here's our first case.

2:44

So what we got here is the sagittal T one weighted Mr

2:50

the axial T two Wave Mr A post gadolinium enhanced,

2:56

uh, scan here.

2:57

And this is the flare scan.

2:59

So T one axial T two flare

3:03

and post gadolinium.

3:05

This is with fat suppression T one weighted scan.

3:11

So what is the most likely diagnosis given the,

3:14

given these imaging findings,

3:15

do you think this is most likely a squamous cell carcinoma,

3:19

a mucus retention cyst, allergic fungal sinusitis,

3:24

inverted papilloma, or a schneiderian polyp?

3:28

So looking at the pathology that's being demonstrated,

3:32

what do you think the most likely diagnosis is?

3:34

If you think it's squamous cell

3:35

carcinoma, answer number one.

3:37

If you think it's a mucus retention cyst, answer number two,

3:40

if you think it's allergic fungal sinusitis,

3:42

answer number three.

3:44

For inverted papillo you're gonna put number four.

3:47

And for a schneiderian polyp put number five.

3:51

So we're um, got about 200 people on board

3:55

and we're going to, uh, see what the

4:00

audience recommends.

4:02

So let's share results.

4:03

And it looks like 68% of the people, uh,

4:09

answered allergic fungal sinusitis.

4:10

And indeed that is the correct answer.

4:13

You notice that on the T one way scan,

4:15

we have areas within the perinasal sinuses

4:18

that are bright on T one as well as dark on T one on T two.

4:22

The predominant abnormality here is dark on T two

4:26

as well as flare.

4:27

In fact, you might think

4:28

that this is aerated sinus just looking at the T two

4:32

and then we get to the post GAD T one

4:34

and we see, no, that's not aeration,

4:36

that's very inspissated secretions

4:39

or allergic, uh, fungal mucin

4:43

that is causing the very low signal on the T two way scan.

4:47

And you see also that the ethmoid sinus is opacified.

4:51

So remember that the signal intensity of the

4:56

secretions in the perinasal sinuses

4:59

is dependent in part on the protein concentration.

5:03

This was beautiful work that was done

5:04

by the late Peter Som in the 1980s in which he aspirated.

5:09

He actually got the ENT doctors to aspirate sinus secretions

5:14

and then measure the protein concentration.

5:17

And what he showed was that this is signal intensity,

5:20

this is the T one and this is the two.

5:22

When you have low protein concentration,

5:25

effectively just fluid, it's gonna be dark on T one

5:28

and bright on T two.

5:30

However, as the protein concentration increases,

5:34

you notice the first thing that happens is

5:36

that the T one becomes bright.

5:39

This is the iso intense line here becomes bright.

5:42

So you'll have a period where it's bright on T one

5:44

and bright on T two, but as those secretions get more

5:49

and more mucinous and and

5:51

and less watery, you come to a point

5:54

where it's bright on T one, but now it's dark on T two

5:58

and when it becomes a concretion,

6:00

effectively like a calcification, it's dark on T one NT two.

6:05

So these are the graphs

6:07

that you should know about protein concentration.

6:09

This also will pertain to things like cranial omas

6:14

or pineal region cysts

6:15

or other things that have high protein content like OID

6:19

cysts for example, the things

6:22

that are hyperdense on ct

6:24

but dark one T two include blood products.

6:27

It's just like that hyper protein tenacious secretions,

6:30

fungus, you may see that with osteos or odontogenic lesions

6:35

and indeed melanin, which may be bright on T one

6:38

and dark on T two from the melanin is often hyperdense on

6:43

CT in part maybe because of it may be hemorrhagic as well.

6:47

So this was a case of allergic fungal sinusitis,

6:50

which is not an aggressive invasive type

6:54

of fungal sinusitis.

6:56

Remember that we have five different varieties.

6:58

We have our non-invasive fungus ball

7:00

or mycetoma, it's usually in the maxillary sinus.

7:03

We have our non-invasive allergic fungal sinusitis

7:06

with the eosinophilia and the um, mucin.

7:10

Um, we have the acute invasive fungal sinusitis.

7:13

Those are usually the patients who have

7:15

diabetic ketoacidosis at presentation

7:18

and are immune compromised

7:19

and they may have mucor or aspergillus.

7:22

Then we have the chronic invasive sinusitis, long standing,

7:26

uh, patients who have chronic rhinoc sinusitis

7:29

and then this unusual chronic granulomatous invasive fungal

7:32

sinusitis that is not usually seen in America

7:35

but more commonly in Africa or Southeast Asia.

7:38

Here's another example on CT of a patient

7:42

who had allergic fungal sinusitis

7:43

and you see the hyperdensity to those secretions

7:47

and there is some bony dehiscence

7:49

because of effectively like polyps.

7:51

It's it's remodeling the bone.

7:54

The five criteria for allergic fungal sinusitis type one

7:57

hypersensitivity often seen with the eosinophilia

8:01

nasal polyposis CT findings of ification eosinophilic mucin

8:06

and a positive sun fungal stain without demonstration

8:10

of invasion.

8:11

Here on the other hand on A MRI with bright on T one,

8:16

this is a turned out to be a mycetoma fungus ball in the

8:20

right maxillary antrum of pacifying it.

8:23

This was one of the cases

8:24

that I saw back when I was a resident

8:27

in which the patient had severe fungal invasive sinusitis

8:32

with mucor mycosis.

8:34

And what you're seeing on this post gadolinium T one wade

8:37

scan is opacification of the right cavernous sinus,

8:41

but absence of opacification in the left cavernous sinus.

8:46

If you look at the carotid artery here,

8:48

faintly seen it's narrower than the normal right side.

8:52

It's got a little irregular margin.

8:54

So this patient had fungal sinusitis with invasion

8:57

of the cavernous science and thrombosis

8:59

of the CCI associated with vasculitis.

9:02

And the neck scan showed MCA infarction secondary to the

9:07

left internal car artery vasculitis from the

9:11

invasive nuclear mycosis.

9:14

Alright, all right, next case case number two.

9:17

Let's move on. Here's the CT scan axial

9:22

original data SAL reconstruction

9:27

MR T one post GAD mr axial

9:31

T one post gad.

9:33

So I'll give you a moment to look over the case CT

9:38

and MR with gad

9:43

most likely diagnosis for this entity.

9:45

Is this a mucosal? Is this pot puffy tumor?

9:51

Is this a dermoid?

9:53

Is this nasal glioma

9:56

or is this a sebaceous cyst?

9:59

So the most likely diagnosis here,

10:01

if you think it's a mucus answer number one,

10:03

if you think it's pot puffy tumor number two,

10:06

if you think it's a dermoid answer number three,

10:09

if you think it's nasal glioma number four

10:13

or a sebaceous cyst number five.

10:16

So let's see how the audience is doing here

10:21

and I think we can end the poll

10:23

because there's an overwhelming share

10:25

that results overwhelming uh, support for pot puffy tumor.

10:29

And that is indeed correct.

10:31

You have a patient who has a frontal sinusitis

10:34

with opacification.

10:36

There's a little divot here out of the frontal sinus

10:39

where the infection has

10:42

entered the soft tissues of the forehead.

10:45

And obviously this pop puffy tumor was thought

10:48

to initially be a tumor

10:49

because it was presenting

10:50

as a soft tissue mass under the skin.

10:54

And the, let me give you a little history here.

10:58

All pot puffy tumor

11:00

forehead edema resulting from osteomyelitis

11:02

of the frontal bone associated with a subperiosteal

11:05

abscess first described by Sur Percible pot in 1768.

11:10

Lemme tell you, they did not have CT scans back then.

11:13

That's why he thought it was a tumor rather than the spread

11:16

of infection from the frontal sinus.

11:19

And obviously when he went to cut it open

11:21

and got that purulent stuff coming out.

11:24

Um, so you have rubor, tumor, calor and doll.

11:28

So redness, swelling, warmth,

11:29

and the tumor in this case is the observable swelling

11:32

of the forehead rather than to any neoplasm.

11:35

And it's a complication of frontal sinusitis.

11:37

So pot puffy tumor, we often call it pots puffy tumor,

11:42

but the gentleman's name was sir Percival pot

11:47

frontal sinusitis, um, is an entity

11:52

that may be associated with the infection going

11:55

superficially and creating a pot puffy tumor.

11:57

But it could actually also extend intracranial

12:01

where you may have an epidural abscess developed from the

12:05

infected frontal sinusitis.

12:06

You see that here.

12:08

If this collection dissects the sinus

12:13

off of the periosteum of the frontal bone, uh,

12:17

it may actually cross the midline.

12:20

And any collection

12:22

that's crossing the midline we assume is going

12:24

to be an epidural, uh, abscess

12:27

or epidural uh, hematoma as the case may be with trauma.

12:32

So you may also see findings of meningitis.

12:36

So look at the flare scan, look at the CSF.

12:39

Is the CSF still suppressed on the flare scan

12:43

or if it's not suppressed, that might imply

12:45

that there's meningitis associated with it.

12:46

Obviously with this type of proximity

12:49

to the superior sagal sinus, you may get sinus thrombosis

12:53

and then have a superimposed venous infarction on top

12:57

of the infection on top of the sinusitis, for example.

13:03

Okay, we're moving on to the next case.

13:05

This patient had previously had a medial antrostomy

13:09

for inflammatory disease

13:11

and what you're seeing is the,

13:13

this is the sagittal cyst T two weighted scan.

13:17

This is the post gadolinium T one wayed scan.

13:20

This is the axial T two weighted scan

13:23

and you can see that we're going through this abnormality.

13:28

And then this is the a DC map of the lesion.

13:33

So patient who had previously had surgery,

13:37

and you can see that the lesion in question here

13:40

that we're looking at is this area here.

13:47

The most ominous feature of this lesion is what is it?

13:51

The dark signal on T two weight imaging.

13:54

Is it the fact that it enhances? Is it the low A DC?

13:58

Is it the eroded bone

14:00

or is it being bright on T two wade scan?

14:03

So on the imaging features of this lesion, which one kind

14:07

of bothers you most?

14:08

Is it the dark signal on T two imaging?

14:11

Is it the presence of enhancing tissue?

14:14

Is it low on a DC?

14:17

Is it eroded bone

14:19

or is it bright on the T two wayed scan, which

14:21

of these is the most ominous feature of this lesion?

14:27

Alright, T two post gad

14:32

T two axial a DC map.

14:36

Alright, we've got over a hundred responses, so let's, uh,

14:39

see what people said.

14:41

Okay, so the, the answer to the question, um,

14:45

by the group is low a DC and I would agree with that.

14:49

Um, the reason why I would agree with

14:51

that is dark one T two, as you know, we just saw a case

14:55

of allergic fungal sinusitis that

14:57

can occur within SPED secretions.

14:59

It can occur with fungal sinusitis,

15:01

it can occur with osteos.

15:03

I gave you all of those differential diagnosis enhancement.

15:06

So enhancement is important

15:09

and solid enhancement is gonna be a pretty good indicator

15:12

that this is neoplastic as opposed

15:15

to an inflammatory process.

15:17

So the fact that this tissue shows enhancement

15:20

is a ominous finding.

15:22

Low A DC, yes.

15:24

However, remember that just as

15:28

epidermoids may have low a DC and it's not necessarily

15:33

because of hypercellular tumor, it's in part

15:35

because of the concentration of protein in the lesion or,

15:39

or the, the content of the lesion.

15:41

Um, you may see in spec secretions

15:44

and things with high protein

15:45

that will have restricted diffusion, eroded bone definitely,

15:49

but a lot of benign tumor, uh,

15:51

benign conditions including mucus seals, including polyps,

15:55

including, um, you know, osteos,

15:59

those things can erode the bone

16:01

and yet be a benign condition.

16:03

Brighton T two, usually that's reassuring.

16:05

So that would be the least.

16:08

So given all of these findings,

16:10

what do you think the most likely diagnosis here is?

16:12

Is this a squamous cell carcinoma?

16:14

Is this an inverted papillo? Is this melanoma?

16:18

Is it lymphoma or is it fungus?

16:20

So our lesion is here

16:22

a relatively dark on the T two showing contrast enhancement

16:26

dark on T two, a little bit of obstructed secretions

16:30

and low on a DC map.

16:32

What do you think the most likely diagnosis is?

16:34

Is it squamous cell carcinoma?

16:36

Is it inverted papillo, is it melanoma?

16:38

Is it lymphoma or fungus?

16:41

So, uh, number one for squamous cell carcinoma.

16:43

Number two for inverted papillo, three for melanoma, four

16:47

for lymphoma, and five that there's a fungus among us.

16:52

See what people say here.

16:55

So let's, uh, share some results

16:58

and we have a mixture of, um,

17:01

different suggestions including squamous cell carcinoma,

17:05

lymphoma, inverted papillo, not

17:07

so much melanoma, not so much fungus.

17:10

So I think that's reasonable.

17:12

All three, the squamous cell carcinoma, inverted papillo

17:14

and lymphoma may look this way.

17:17

If you're going with the most likely diagnosis

17:20

by the numbers, the most likely cancer

17:23

of the perinasal sinuses is squamous cell carcinoma.

17:27

So that would be the best diagnosis here.

17:30

It's not a particularly good location for inverted papillo,

17:33

which usually occurs along the, uh, common wall

17:37

between the maxillary sinus and the nasal cavity

17:41

or along the septum pum.

17:45

This area, which is effectively in the ethmoid sinus,

17:48

is not the best location

17:50

for an inverted papillo, not classic.

17:53

So our answers are low, a, d, c

17:59

and squamous cell carcinoma by numbers.

18:02

It looks like there's some, I got some chat things.

18:04

Let's see. Um, immer, no, not for me.

18:07

Okay, no questions at the moment.

18:12

Question and answer. What is a schneiderian polyp?

18:15

Schneiderian polyps are, uh, types of polyps

18:18

that are included with inverted papilloma

18:21

and it refers to the histopathologic features

18:25

and, um, I'll move forward

18:27

because they ask about the next, the answers.

18:31

All right, so here is a graph that you see from head

18:35

and neck surgery in oncology.

18:37

Justin Jain Shaw, who's from Memorial Sloan Kettering.

18:41

And you notice that the most common of the cancers of the,

18:44

uh, nasal cavity

18:46

and perinasal sinuses are,

18:47

is indeed squamous cell carcinoma.

18:50

And then we have this kind

18:51

of other category which are und differentiated cancers.

18:54

We have melanoma, which is the pink here,

18:57

minor salivary gland tumors, et cetera.

19:00

And, um, the cyto nasal

19:02

and differentiated carcinoma, uh, one of the more aggressive

19:06

of the cy nasal cancers.

19:08

All these kind of lookalike except for melanoma,

19:11

which hopefully you'll see

19:12

as bright on T one if it has enough melanin

19:15

content within it.

19:17

Es neuroblastomas are the ones

19:19

that are usually in the upper nasal cavity and ethmoid sinus

19:21

and cribriform plate that grow most frequently intracranial.

19:26

And the characteristic feature of

19:27

that is the peripheral cyst associated with the anesthesia

19:32

that happens with other cancers,

19:33

but it, the, the highest rate is

19:35

with anesthesia neuroblastomas

19:37

or what we sometimes use the term olfactory neuroblastomas.

19:43

Here's the 80% rule.

19:44

80% of sinus cancers occur

19:48

in the maxillary antrum.

19:50

Of those 80% are squamous cell carcinoma.

19:52

Of those 80% erode bone

19:54

and 80% have a history of chronic sinusitis.

19:57

Moving on next case,

20:03

CT scan axial raw data, coronal reconstruction,

20:11

least likely diagnosis number one,

20:16

UL ominous polyangiitis.

20:18

Number two, fungal sinusitis. Number three, cocaine abuser.

20:23

Number four, syphilis number five, Ella.

20:28

So for this imaging finding that you're seeing

20:33

what is the least likely diagnosis,

20:36

if you think it's gran ominous polyangiitis, GPA

20:41

number one if you think it's fungal sinusitis.

20:44

But number two, if you think it's cocaine

20:47

abuser, put number three.

20:48

If you think it's syphilis, put number four.

20:50

And if you think it's Klebsiella, put number five.

20:56

Okay, So let's, uh, share the results.

21:02

And, um, the, the correct answer here is fungal sinusitis,

21:06

which I guess is the second most common answer here.

21:10

Cupsi is one of the bacteria

21:14

that will collapse your nasal septum.

21:17

So the finding here is nasal septal perforation and erosion

21:21

and you have all that soft tissue.

21:23

So in yesteryear we would often use the term wagoners,

21:27

but now we're using granulomas polyangiitis.

21:30

That's a pretty frequent cause.

21:32

Um, of demonstration of sinus

21:36

involvement by wagoners.

21:38

Fungal sinusitis doesn't often cause septal perforation

21:43

cocaine abuser at,

21:45

in East Baltimore at Johns Hopkins's probably the most

21:47

common thing, and we probably have around a 10 to 20% rate

21:51

of patients that you're reading their trauma head CT

21:54

or motor vehicle collision.

21:55

And you see nasal septal perforation.

21:58

So cocaine or other drugs, um, syphilis, uh,

22:02

saddle nose deformity associated with syphilis

22:06

and leprosy, those are known causes as well.

22:12

So the correct answer was fungal sinus.

22:15

This is another one of the entities that can lead

22:17

to a gran ominous sinuses as well

22:21

as inflammation in the orbit.

22:23

So wagoners also may have inflammation in the orbit

22:28

associated with a nasal septal perforation.

22:30

When you put those two together, you will come up

22:34

with the granulomas polyangiitis as well as sarcoidosis

22:38

as another of the etiologies.

22:40

It can occur after trauma, it can occur

22:43

with a nasal septal hematoma that erodes the bone.

22:47

So there's lots of differential diagnosis

22:50

for nasal septal perforation.

22:52

Here I have a relatively large listing,

22:55

remember I talk about vitamin C

22:58

and D, vascular, infectious, traumatic, acquired metabolic,

23:01

osteopathic, neoplastic and drug.

23:03

And here we have our trauma cau causes,

23:05

we have an inflammatory causes, lots of those collagen,

23:08

vascular disease, infectious causes, syphilis, et cetera.

23:12

Uh, you notice that CCI is not listed here,

23:16

but it is one, uh, does mention fungal,

23:19

but that's the aggressive fungal infections, neoplasms,

23:23

carcinoma, t-cell lymphomas,

23:24

and then all these toxic, uh, etiologies.

23:30

Alright, I wanna make a a point here

23:34

that on this case you saw

23:35

that there was some dehiscence along the laminate prepara.

23:40

And when I am reading a sinus CT

23:44

where I know the patient is going to surgery

23:48

or is about

23:50

or has gone to surgery, there's four critical areas

23:53

of dehiscence that you might wanna look at

23:56

and put in your reports.

23:58

The four critical areas

23:59

of dehiscence are the laminate prepara

24:02

as you see here along the medial orbital wall

24:05

because if it's dehi

24:08

and the surgeon is going in to clean up that ethmoid sinus,

24:12

there is that possibility

24:13

that they would perforate into the orbit

24:15

and lead to an orbital hematoma.

24:17

The second is the cribriform plate.

24:18

Here you see a defect in the cribriform plate.

24:21

In fact, this patient actually has a meningocele

24:24

that's extending intracranial.

24:26

So post-op, if they take down the middle turbinate, remember

24:30

that the middle turbinate has a connection

24:33

to the cribriform plate as well as

24:36

to the lateral orbital wall.

24:37

And if they're removing the middle turbinate,

24:39

there's a chance that in that removal they lead

24:43

to a cribriform plate

24:44

or a laminate prepara basal lamella, uh, injury

24:49

to the medial orbital wall or the, or the skull base.

24:53

And that potentially could be a source of CSF leakage,

24:56

but it also, if it's de hissin, could lead

24:59

to the next time they operate, uh,

25:01

potential intracranial perforation

25:04

the optic nerve and canal.

25:05

It's interesting how often you will see that the optic nerve

25:10

at the optic canal has no bone around it

25:14

in the sphenoid sinus and, and

25:17

or posterior ethmoid region,

25:18

depending upon whether you have an a node cell.

25:21

So I often will, will comment on the dehiscence

25:25

of the wall of the optic nerve if they are contemplating

25:29

sen ethmoidal surgery and more

25:31

and more that's usually, uh, associated with, um,

25:36

cell tumors or pituitary adenoma resection, for example.

25:39

And then finally the carotid canal.

25:41

So here we have the dehi carotid canal.

25:44

You can see the enhancing carotid artery.

25:46

There's no bone overlying it again, at our institution,

25:51

they will do a 3D reconstruct 3D

25:56

dataset of the perinasal sinuses prior to

26:01

pituitary adenoma surgery

26:02

because they want to know where the carotid arteries are

26:06

with the potential for injury if they're doing an endoscopic

26:09

removal of a pituitary adenoma.

26:11

So they wanna see the walls of the carotid arteries

26:15

and actually then also the tumor's

26:17

relationship to the carotid artery.

26:19

So these are the four things you might wanna think about

26:22

adding to your report when you look at a sinus case

26:25

that's either about to be operated on

26:27

or has previously been operated.

26:30

Okay, let's move on.

26:32

Uh, next case, most likely diagnosis,

26:41

CT scan axial and coronal reconstruction.

26:45

Most likely diagnosis is this most likely an antal polyp?

26:50

Is this most likely a mucus retention cyst?

26:52

Is this most likely allergic fungal sinusitis?

26:56

Is it inverted papilloma, or is the old Schneider polyp?

26:59

Once again. So if you think it's an intracraneal

27:03

pop, you'll put number one.

27:05

If you think it's a mucus retention cyst,

27:06

you'll put number two if you think it's allergic

27:09

fungal sinusitis.

27:10

Number three, if you think it's an inverted

27:13

papilloma, put number four.

27:14

And if you think it's a Schneider pop, put number five.

27:23

All right, tricky case.

27:26

Um, so most people put antal pop

27:29

and that is not the correct answer,

27:33

although this looks exactly like an antal pop.

27:37

So why, why is this not an InterQual pop?

27:41

Um, the, the density of this lesion is

27:44

what should give you pause

27:46

that this is not like a typical pops.

27:49

Pops generally are lower density on the CT scan.

27:52

They may even be fluid density.

27:54

Remember that mucus retention cysts

27:56

and pops of the maxillary antrum often

28:00

are very liquidy and low density.

28:03

The key here to this case was

28:05

that this looks like hyperdense.

28:08

Here's the mucosa here peripherally

28:13

that is less dense.

28:14

This was histopathologically

28:16

and inverted papillo, so

28:18

that was the second most common answer.

28:20

So very good to those people.

28:22

The intracraneal pop as you see here, more likely

28:25

to be a low density lesion,

28:27

but it does go through the osteum of the maxillary sinus.

28:32

Usually we say it's the inferior osteum

28:34

or the accessory osteum,

28:35

but it does then project into the nasal cavity.

28:39

That's sort of the choanal portion of it.

28:41

And then it can even project back into the nasopharyngeal

28:45

airway posteriorly.

28:46

So from here it may project posteriorly

28:50

as a nasopharyngeal soft tissue mass.

28:54

In this case, again, look for a lower density to suggest

28:58

that it's antal pop as opposed to the inverted papilloma.

29:02

Here is the, uh, an inverted papilloma, as I mentioned.

29:05

It usually forms along the common wall

29:08

of the maxillary antrum and the nasal cavity.

29:12

And from there it can grow into the maxillary science

29:15

or into the nasal cavity or both.

29:17

Here you see a little bit more growth into the nasal cavity

29:20

than into the maxillary antrum.

29:22

It will show solid enhancement, not peripheral enhancement.

29:25

Peripheral enhancement.

29:27

More common with the antal polyp, not solid enhancement.

29:31

And you can see that intermediate signal intensity

29:34

on the T two scan.

29:37

There are two of inverted papilloma

29:41

that we say are relatively pathognomonic to suggest

29:46

that specific diagnosis.

29:48

One is this little bony bar

29:51

upon which the tumor may be fixed.

29:54

So if you see that hypostatic bone

29:58

and the tumor seems to be centered around

30:01

that hypostatic area,

30:05

that would be an indicator for an inverted papillo.

30:09

Again, usually the common wall between the maxillary antrum

30:13

and the nasal cavity

30:14

or along the

30:17

midline nasal septum.

30:20

The other feature that we say is relatively pathognomonic

30:24

for a inverted papilloma is this cerebra form.

30:28

Look to it, it, it has almost a look like gyre

30:32

and soci within it that you see here,

30:34

or gray and white matter.

30:36

And you can see the enhancement, uh,

30:39

as you, as you see here.

30:40

Maybe this is the cortex

30:41

and this is the underlying white matter.

30:44

That imaging pattern is

30:49

more typical of inverted papillo than anything else.

30:52

Now that said, we always worry with inverted papillo

30:55

because there is that high rate of concurrence

30:58

of squamous cell carcinoma at about 15%.

31:02

So these tumors are

31:05

resected in their entirety and with a margin

31:08

because of the worry

31:09

that there may be underlying squamous cell carcinoma.

31:14

Unfortunately, the squamous cell carcinoma has the same

31:18

relative imaging features as that, um,

31:21

of the inverted papilloma.

31:22

So it's not as if you can look at this

31:24

and say, oh, this is, um, you know,

31:26

this one has squamous cell versus this one that does not.

31:34

Okay, next case, question six, most likely diagnosis.

31:41

So we have, uh, axial CT

31:45

and a coronal ct.

31:46

You see that, um, contrast was administered here.

31:55

What do we got here? Do we have orbital cellulitis,

32:00

periorbital cellulitis, post septal cellulitis,

32:05

subperiosteal abscess, or none of the above?

32:10

So this case, what are we looking at?

32:13

Are we looking at orbital cellulitis?

32:15

Are we looking at periorbital cellulitis?

32:18

Are we looking at post septal cellulitis?

32:21

Are we looking at a perio subperiosteal abscess

32:25

or none of the above?

32:32

All right, so we're moving right along here.

32:38

Alright, let's see. So, uh, 66% of people

32:42

put subperiosteal abscess

32:44

and that is ding ding, ding, the correct answer.

32:47

Let's go back to the original images.

32:49

So most of the cases of inflammation of the orbit

32:54

occur secondary to things around the lids bites

32:58

or, you know, uh, lacrimal problems, et cetera,

33:04

lytic things in the forehead, et cetera,

33:07

and sinusitis.

33:09

And with sinusitis, it's most commonly the ethmoid sinus

33:13

that has that ability to spread to the orbit.

33:19

Why is that? So, um, you see this a lot with kids

33:22

because there are areas of dehiscence along the lateral wall

33:27

of the ethmoid sinus, and even in adults it occurs.

33:31

And if you think of the, um, lamina pap,

33:37

the medial orbital wall of the orbit being that thin,

33:40

that we would call it haa paper thin, um,

33:45

you might expect that along those channels

33:48

that have vessels going into it, that you might have, um,

33:52

a root for spread from ethmoid sinusitis to the orbit.

33:58

Additionally, remember

34:00

that we have the anterior ethmoid artery

34:02

and the posterior ethmoid artery that enter the, um, the,

34:07

that go between the orbit

34:08

and the ethmoid sinus through those areas of

34:12

vascular channels that communicate

34:14

between the sinus and the orbit.

34:17

So here we have this collection

34:20

and you notice that it's displacing the

34:21

medial rectus muscle.

34:23

The superior oblique muscle is enlarged compared

34:26

to the normal superior oblique muscle.

34:28

And we have this load density collection here,

34:31

and that is accounting for here.

34:33

This is probably the medial rectus muscle,

34:35

and this is the collection with these collections.

34:41

We call them subperiosteal abscesses,

34:44

even if we do not see peripheral enhancement.

34:48

So this is one of the locations that we would,

34:50

you still use the term abscess,

34:52

even though on the post contrast scan you don't see a walled

34:55

off, um, collection

34:59

with peripheral enhancement.

35:01

Most of the time nowadays, these lesions are treated with,

35:07

um, intravenous antibiotics

35:09

and close observation in the hospital.

35:14

And if it does not quickly resolve,

35:17

then they usually are going

35:19

to treat the sinus disease endoscopically

35:23

and try to address the primary pro infection

35:27

that's causing this problem with the sinus disease.

35:32

When I was a resident and

35:33

before endoscopic sinus surgery was, um, so popular, um,

35:38

they would go medially along here and under the periosteum

35:42

and try to drain these surgically,

35:45

but that's not, this is no longer primarily a surgical

35:50

orbital procedure.

35:53

It's let's, let's give you know,

35:55

high dose intravenous antibiotics, see

35:57

how the patient does if they've improve, continuing them

36:01

as an outpatient on oral antibiotics.

36:04

If they don't improve rapidly,

36:06

then consider endoscopic science surgery

36:08

to re reduce the infection in the ethmoid science.

36:13

Generally the, the ENT docs don't like operating

36:17

when there's active acute sinusitis

36:21

because of the potential for spread by virtue

36:25

of their surgical procedure.

36:28

Okay, so this was a, um, subperiosteal abscess, uh, note

36:32

that post septal cellulitis

36:35

and orbital cellulitis are the same entity, the inflammation

36:38

that gets into the orbit.

36:40

Um, here's an example.

36:41

Post septal cellulitis on the left side with infiltration

36:44

of the orbital fat.

36:46

You notice that the orbital fat on the left side is more

36:49

dense than the orbital fat on the right side.

36:50

There's all kinds of episcleritis

36:52

that's happening here as well.

36:55

Um, here's a collection that you see superiorly,

36:58

a subperiosteal abscess and this orbital septum.

37:02

All the diagrams always show it on a sagittal scan.

37:06

What we usually, um, want to see it is in an axial plane.

37:11

And this is the demonstration

37:13

of the orbital septum in this case.

37:15

Inflammation of the orbital septum, still called um,

37:19

periorbital cellulitis.

37:21

Here we have the collection

37:22

of the subperiosteal abscess in the,

37:25

from the ethmoid sinusitis,

37:27

but here's the normal septal tissues that you see here

37:30

and here, orbital septum.

37:36

There is a classification for

37:40

the degrees of orbital infection.

37:44

We have the channeler classification.

37:46

Uh, number one is pre septal cellulitis,

37:50

what we call the peri periorbital cellulitis,

37:53

post septal cellulitis

37:54

or orbital cellulitis, a subperiosteal abscess.

37:57

So this was a case of grade three Chandler classification.

38:02

Uh, four is actual orbital abscess

38:05

where the lesion is in the intracon space, for example.

38:09

And then as an example of that mucor mycosis case,

38:13

we have cavernous sinus inflammation and

38:15

or thrombo phlebitis.

38:18

So I'm just gonna refer to the question here.

38:20

In your practice, do you proceed to MR with contrast

38:23

for cases of suspected inverted papillo on unenhanced CT

38:26

or inject contrast on ct?

38:29

Uh, we're going with MRI, um, mainly

38:31

because there is that potential for perineural spread

38:35

of tumor back through the tego palatine fossa as well

38:40

as intracranial spread.

38:41

And both of those are much better seen on post GA MR

38:45

than with ct.

38:46

So it's pretty rare for us to do a contrast enhanced CT

38:50

for neoplasms

38:51

or for suspected intracranial spread of an infection.

38:55

Canula have orbital subperiosteal abscess without concurrent

39:00

orbital cellulitis.

39:02

In general, what you see is the infiltrate, uh,

39:05

the infiltration and edema of the intracon fat associated

39:09

with the, um, the subperiosteal abscess.

39:13

So most of the time you get this infiltration of the fat.

39:17

So it is, um, you know, it is with concurrent,

39:22

um, orbital cellulitis,

39:24

but with the Chandler, oops, the Chandler classification,

39:27

we would call it grade three.

39:31

All right, moving on to the next case.

39:35

Here we have, uh, CIS imaging T two weighted

39:38

high resolution imaging.

39:40

This is the traditional coronal T two wade scan,

39:45

post GAD T one sagal scan,

39:49

the axial T two weighted imaging and a post GAD axial scan.

39:54

So here we have a, um, child

39:58

and we have T two way in imaging high resolution as well

40:02

as post gadolinium enhanced scans.

40:08

What term should not be used

40:11

for this lesion should not be used.

40:13

Uh, cephalic sino with modal cephalic, seal,

40:18

meningocele, basal ceal or none of the above.

40:22

They're all good. So which of these

40:25

is the inappropriate term for this lesion?

40:28

Would it be Al Cephas seal sino with modal,

40:33

ceal, meningocele, basal ceal,

40:39

or none of the above?

40:40

They all apply to this lesion.

40:46

Okay, so for this case, um, the key here is the difference

40:50

between tal and basal.

40:54

And the distinction is that the basal cephaloceles,

40:57

obviously base of the skull are generally invisible

41:02

to the naked eye to observation externally,

41:09

al Cephaloceles are ones that protrude beyond the

41:13

skull, such that you see them

41:18

like the pots, puffy tumor in the forehead, et cetera.

41:20

And those are usually nasal ethmoidal cephas seals

41:24

that will project through the frame and secum

41:28

or other pathways

41:30

and project as a visible to the,

41:34

to the naked eye lesion.

41:36

So that's tal as opposed to basal

41:39

where it's invisible to you.

41:40

So the correct answer here is that this should not,

41:43

this is not as tal no one would be able

41:45

to tell what's going on despite the

41:47

huge size of this lesion.

41:50

And this was indeed a, um, congenital, um,

41:54

a congenital, uh, encephalocele.

41:57

Now the, the term cephaloceles kind of a, you know, um,

42:03

indistinct, let's say, um, usually we wanna know whether the

42:08

ceil contains meninges and fluid and or brain tissue.

42:13

So defend, depending upon whether you think this is purely

42:16

meninges and fluid, you might use the term meningocele.

42:21

If you think that there is indeed brain tissue gray matter

42:24

that's herniating through as well, you would use the,

42:27

the term encephalocele.

42:30

And if it's both the meninges, the fluid

42:32

and the brain tissue,

42:33

we would use the term meningo encephalocele.

42:37

The sloppy term or the,

42:40

or the lazy term would just be a encephalocele in which

42:43

you're not making that distinction.

42:45

Now, um, let me just see whether I can, um,

42:51

go with the answer in the chat.

42:54

Do you think that this, um, cephalic e

42:58

is congenital?

43:00

If you think it's a congenital lesion, please answer

43:04

yes in the chat if you think that it no, it's

43:08

developmental or secondary to operative or trauma

43:12

or other defect in the skull base, you would answer no.

43:17

So just in the chat you think this is congenital, say yes.

43:20

If you think no, this, this is, um, you know, developmental

43:24

or post-op or other cause say no.

43:29

So I'm looking in the chat and there's a lot of yeses

43:32

and that is indeed the correct answer.

43:34

And one of the reasons why, you know,

43:36

it's the correct answer is you may have noticed

43:38

that there's missing portions of the splenium

43:41

of the corpus callosum

43:42

and the rostrum of the corpus callosum.

43:45

Identifying other congenital lesions that would suggest

43:48

that this is a congenital ence foal.

43:51

Here is that CT scan where I was saying

43:54

that there was absence of the cribriform plate.

43:56

And look at this same patient brain tissue and fluid

44:01

and meninges assumed to be present

44:05

meningo encephalocele through the cribriform plate.

44:09

This was a post-op patient

44:11

who had a defect in the cribriform plate.

44:14

This is a different patient T one weighted scan.

44:17

Notice the puckering

44:18

of the brain tissue towards this gap in the

44:22

cribriform plate.

44:23

Post gadolinium a little bit of an in, uh, enhancement

44:26

of inflammatory change.

44:28

This is actually the collection here and here

44:33

and where the collection is in the brain tissue is you don't

44:36

see the um, you don't see the, uh, enhancement.

44:41

So cephaloceles are a cause, uh, potential cause

44:44

of CSF rhinorrhea.

44:46

And um, as you see here,

44:49

congenital most common occipital associated

44:52

with potentially are RO qre three malformations post-op,

44:57

post-trauma, sometimes idiopathic intracranial hypertension

45:01

or pseudotumor cerebra may be associated with celi,

45:05

cephaloceles and meningocele.

45:07

Um, you all, that's why we look at the meles cave region

45:10

to see where that's associated.

45:12

And some tumors also may cause, um, CSF rhinorrhea

45:16

and or cephalic cell.

45:19

Okay, next case CT scan.

45:24

We have a corona recon corona reconstruction

45:27

from the axial data.

45:28

And here's the axial scan most likely diagnosis here.

45:32

Is this a mucus seal? Is this a mucus retention cyst?

45:36

Is it silent sinus syndrome?

45:38

Is it a hypoplastic maxillary antrum

45:42

or is it a polyp?

45:44

So given, uh,

45:46

question number eight is, is this a mucus seal?

45:48

If so, answer number one.

45:51

If you think it's a mucus retention cyst,

45:52

we're gonna answer number two if you think it's a

45:54

silent sinus syndrome.

45:56

Number three. Number four for hypoplastic maxillary sinus.

45:59

And number five a polyp.

46:02

So obviously the abnormality is in the left maxillary sinus

46:08

zo the audience.

46:13

All right, so 73% of y'all went with silent sinus syndrome

46:17

and that is indeed the correct answer.

46:20

Why is this not a just a hypoplastic maxillary sinus?

46:24

Well, the imaging findings that you note,

46:27

no doubt is the puckering inward

46:29

of the posterior lateral wall of the maxillary

46:32

sinus associated with the proliferation of the fat.

46:35

And usually the floor of the

46:39

orbit ipsilateral is depressed.

46:44

And the common

46:47

clinical finding here is enophthalmos

46:49

because everything's getting sucked in

46:51

and the the globe actually, um,

46:55

becomes more inwardly displaced as the sinus is

47:00

progressively decreasing in volume.

47:02

So this is at a source of enophthalmos

47:05

and, uh, chronic sinusitis.

47:07

This on the other hand is a patient

47:09

who has a hypoplastic maxillary antrum.

47:13

You notice in this case that the walls of the maxillary bone

47:18

are actually thickened associated with that

47:21

hypoplastic maxillary antrum

47:23

and the floor of the orbit is not depressed.

47:26

Here's another hypoplastic left maxillary antrum.

47:31

Uh, although this is bone window, you see

47:33

that there's no proliferation of the fat that is associated

47:37

with silent sinus syndrome.

47:38

So silent sinus syndrome,

47:39

usually you see complete opacification

47:42

of the maxillary antrum.

47:44

This was a little bit unusual in

47:45

that it wasn't completely opacified

47:47

and we call it also the ectatic sinus as it kind

47:52

of collapses on itself.

47:55

And um, this is a manifestation of a chronic sinusitis

47:59

with reduced pressure leading to the walls collapsing inward

48:04

and compensatory enlargement of the perianal fat.

48:08

So silent sinus syndrome, usually with an opacified sinus.

48:15

Okay, we're gonna end on this one.

48:16

It's um, sort of a classic case

48:19

and I wanted to show it in the, uh, session

48:23

sag T one way scan.

48:24

This is a MRA that was performed

48:30

because of the suspicion of an aneurysm.

48:34

And this is a t two way and this is actually a haste image

48:37

'cause the patient was moving all over the place.

48:39

But, uh, subtlety one MRA

48:43

and haste image,

48:48

is this most likely a mucus seal?

48:51

Is it a thrombo aneurysm?

48:53

Is it a schwannoma, is it an epidermoid

48:57

or is it none of the above?

49:00

So this lesion that we're seeing here is this most likely a

49:02

mucus seal, a thrombo aneurysm, a

49:09

an epidermoid

49:11

or none of the

49:13

above final case.

49:17

So this is a petras apex, uh, case

49:20

and the petras apex is very much like the paranasal sinuses.

49:24

So I thought it was okay for me

49:26

to put it in here in a cy nasal talk.

49:30

And uh, petre apex may be pneumatized,

49:32

it may not be pneumatized when it's pneumatized.

49:35

Um, it has the potential for petre ap sitis

49:39

for petre apex mucus seals,

49:41

and for an inflammatory reaction from bleeding that leads

49:46

to a giant cell reaction

49:49

and what we, uh, will call a cholesterol granuloma.

49:53

So the correct answer here is none of the above.

49:56

This is an example of a cholesterol granuloma,

50:00

which is typically bright on T one and maybe bright

50:03

or dark on T two depending upon the protein slash blood

50:07

slash cho content of it.

50:10

You see, uh, here on the T one it's in the Petra apex,

50:14

it expands the petre apex.

50:16

So you see that here.

50:19

The differential diagnosis is, is all of these a mucus seal

50:24

of the apex could look just like this

50:29

as well and it's in the differential diagnosis,

50:32

but cholesterol granulomas are much more common

50:36

and they're more heterogeneous,

50:37

particularly on T two A scanning most of the time

50:40

with mucus seals.

50:41

It's uniform signal intensity throughout the mucosal.

50:46

Here you've got a little bright area,

50:48

you got a little darky,

50:49

you got a little peripheral rim here of black.

50:52

Is that hemosiderin or is that the bone?

50:55

That's pretty typical of a cholesterol granuloma,

50:58

not so much a mucosal.

50:59

The reason why we have the MRA is

51:01

to exclude a thrombo aneurysm

51:03

because your petre carotid artery courses right by here

51:07

and if you have a partially thrombo aneurysm,

51:11

you could have signal intensity that looks like

51:15

blood products that will simulate a cholesterol granuloma in

51:18

this case bri on T one

51:20

and it may be any, any signal intensity on the T two.

51:25

Remember that thrombo aneurysms may have

51:27

that same layering effect, laminated appearance

51:32

that you can see with a cholesterol granuloma and

51:35

therefore could simulate that as well.

51:37

Not likely gonna be a schwannoma,

51:39

not in the petri apex epidermoid.

51:41

So that's fair, right, because they may be bright on T ones.

51:45

The so-called white epidermoids, most

51:48

of them are dark on t, on T one.

51:52

Um, and look kind of like dirty CSF on the,

51:56

on the uh, flare.

51:58

Most of them however, are very bright on the T two.

52:01

So this signal intensity would argue against an epidermoid

52:04

of the petrich apex.

52:06

Epidermoids can occur anywhere in these bones,

52:08

so it's fair again,

52:09

we would hopefully have a diffusion weight scan,

52:12

which might help us remember,

52:13

however that diffusion weight scans in the presence

52:16

of hemorrhage get very confusing to interpret

52:19

because it looks bright

52:21

and it may look like it has dark a DC, but it's really not.

52:24

It's, you know, blood products can do that.

52:27

So, um, in this case the correct answer was none of the

52:30

above because this was a cholesterol granuloma

52:33

of the Petri apex.

52:35

So at this juncture, I am happy to

52:41

answer any and all questions about Cy nasal imaging.

52:46

Uh, I will put in a couple of plugs if you don't mind.

52:49

Um, and that is, uh, on our MRI online modality website,

52:55

you have a case bank of 100

52:59

brain, 100 spine and 100 head

53:02

and neck cases with multiple choice questions

53:05

that I've created as part of a effort to

53:10

have MRI online as, as one of your sites that you go to

53:13

for case, uh, for case review, for board review, review.

53:16

So if you, you know, are a little shaky in your Noro, um,

53:20

come see me at Johns Hopkins

53:22

or alternatively go to MRI online

53:24

and they have, uh, material there

53:26

and um, they are building a larger

53:28

and larger, uh, case bank with multiple choice questions

53:33

to simulate the boards

53:34

and uh, that's probably gonna be appropriate

53:37

for the next couple years until we return to the oral board

53:41

format with, uh, hot seat.

53:45

So, um, I'm gonna go to the q and a

53:49

and see where there any questions for me?

53:52

Okay, questions the answer. Excellent.

53:54

Uh, question, can susceptibility imaging help in the

53:58

diagnosis of cholesterol granuloma?

54:02

So most of the time the blood products

54:07

or the brightness is bright on T one

54:11

and bright on T one is met hemoglobin

54:15

and met hemoglobin does not have

54:18

proton relaxation enhancement

54:20

unless it's in the extra, uh, in the intracellular form.

54:24

So remember that in order to see susceptibility artifact,

54:29

you have to have a difference on the signal intensity or,

54:33

or the iron content inside the cell versus exce

54:37

outside the cell or inside the brain versus in the

54:39

extracellular space.

54:41

So if the blood products are bright on T one

54:44

and bright on T two, that's the extracellular hemoglobin

54:47

phase where you have proton electron dipo dipo direction,

54:50

but you do not have proton relaxation enhancement,

54:53

which is the T two shortening effect.

54:55

So just a quick review of hemorrhage.

54:59

Met hemoglobin has proton

55:04

electron dipod dipo interaction, which leads

55:06

to T one shortening,

55:07

which makes it bright on a T one way scan,

55:10

having blood intracellular

55:12

and not extracellular leads to a bar magnet effect

55:17

of the difference in charge between in the cell versus

55:20

outside the cell, which leads

55:21

to proton relaxation enhancement,

55:23

which leads to T two shortening.

55:24

Once you have cellular lysis and it's extracellular

55:27

and hemoglobin, you no longer have proton

55:29

relaxation enhancement.

55:30

It's no longer dark on T two

55:32

and that's why it is bright on T two from water content.

55:36

So a little digression there into hemorrhage,

55:39

but appropriate.

55:41

Um, hey, what do circle of voice

55:43

and your background stand for COW?

55:46

Um, circle of Lewis I think. And that was the MRAI

55:51

Think it's the picture of your cows behind you, Dr.

55:53

Oh my cows behind me. People wanna know about my cows.

55:55

Those are bulls and this is my, uh, Picasso lithograph

56:01

and uh, if you wanna read about it, you can call,

56:04

you can look up, uh, Picasso's bulls,

56:07

but effectively what I've interpreted this to be is

56:10

that this is the progression

56:11

of Picasso's artwork going from initially charcoal drawings

56:16

to, uh, realism

56:18

and then he converts to cubism over the course of time.

56:22

This is more cubic cubism.

56:24

And then if you look over here,

56:26

he got really minimalistic at the end

56:28

and he just did line drawings.

56:30

So this is the sort of the history of

56:32

Picasso's interpretation and how he drew bulls.

56:36

And this is Picasso's, uh, signature right here.

56:39

So, okay, what did the cow in the background please,

56:43

could you explain the features the surgeon needs

56:45

to know in our cy nasal CT reports?

56:48

Okay, so, um, as I said, most of the time the,

56:52

the surgeon needs to know whether

56:53

or not there are any areas of dehiscence.

56:56

The endoscopic science surgery

56:58

nowadays is basically a medial antrostomy with removal

57:02

of the young snake process and a potential ethmoidectomy.

57:06

The vast majority of the surgeries,

57:08

they will sometimes go into the sputum ethmoidal recess

57:11

and relieve obstruction for the sphenoid science

57:14

and posterior ethmoid sciences.

57:16

So that said, the main thing are the areas of dehiscence

57:20

around the ethmoid sinus

57:22

that potentially could be the cribriform plate superiorly

57:27

and the laminate prepara laterally,

57:30

it's only if they're going into the senal ethmoidal recess

57:32

is that you would worry about those at dehiscence in the

57:35

carotid artery of the optic nerve.

57:37

Now, the other things that they want to know is,

57:41

is the ate process opposed

57:44

or attached to the orbital floor or medial orbital wall?

57:49

There are times when that occurs

57:52

and if they're going to remove that ate process

57:56

and do the medial, an medial antrostomy

57:59

and they rip that ate process

58:01

and pull on it, then they're pulling on the orbital floor

58:05

or the medial orbital wall and you can have that dehiscence

58:07

and then bleeding into the orbit, uh, orbital hematoma.

58:10

So they wanna know about the ate process,

58:13

whether it's just hanging free as it does 90% of the time,

58:18

or is it bending over to the orbital floor

58:21

or even to the medial orbital wall of the laminate, um, aia.

58:26

So those are the the main things they wanna know.

58:28

Please explain question two again. Oh my god.

58:33

Um, Ashley, can you go back to question two?

58:36

I don't remember which one that was.

58:38

Okay, yeah, well she's doing that.

58:40

Are there any particular aspects

58:41

of the bone involvement in Cy nasal pathology

58:44

that are specific or should guide our diagnosis?

58:46

So I mentioned that that bony bar is a pretty typical

58:49

finding of, uh, the patients who have inverted papilloma.

58:54

Clearly if you have a popcorn calcification like

58:59

involvement of the bone,

59:01

then you're talking about the conroy lesions.

59:03

Remember that the nasal septum is mostly cartilage and

59:06

therefore you have and KDRs you have conjure sarcomas,

59:10

you have benign conduit lesions of the, uh, nasal septum

59:15

that can occur and will point

59:17

to a specific diagnosis from the standpoint of

59:21

other sarcomas osteosarcomas or, or, um,

59:25

or, um, Ewing sarcoma.

59:29

No specific imaging features in that situation.

59:32

The other pathology that is

59:35

typically a diagnosis you can make is bright on T one in an

59:39

aggressive lesion in the cyto nasal cavity.

59:42

We're gonna go with melanoma intracranial lesion

59:45

with a system around the periphery.

59:47

We're gonna go strongly with olfactory, neuroblastoma

59:50

or anesthesia neuroblastoma, all the other ones, the SNS

59:53

and the other undifferentiated carcinomas

59:56

and adenocarcinomas, not so much perineural spread.

60:00

We're gonna go with adenoid cystic carcinoma as the

60:04

sanos salivary gland lesion

60:06

that can occur in the sano nasal cavity

60:08

that has the highest rate of perineural spread,

60:10

particularly into the tega palin fossa.

60:13

So for that,

60:14

if I see peroneal spread into the tego palatium fossa

60:17

and start following the fifth granial nerve,

60:19

I'm gonna suggest that this could be adenoid cystic

60:21

carcinoma with, um, perineural spread lymphoma,

60:26

usually more of a ho homogeneous lesion rather than

60:29

the squamous cell carcinoma.

60:31

Kind of bland that would help.

60:33

Can you please explain how

60:35

to differentiate supraorbital ethmoid air cells from frontal

60:38

becomes very confusing at times.

60:41

Um, I usually am able

60:45

to kind of make

60:46

that distinction based on usually the sagittal

60:50

reconstruction that you can see the communication

60:53

of the air cells with the ethmoid going above the,

60:58

the, um, the orbit.

61:00

Same thing is true with the anodes cell.

61:02

So I reem I referred to the anodes cell,

61:06

which is an ethmoid air cell that actually extends superior

61:10

to and sometimes even posterior to the sphenoid size.

61:14

Much be better seen on the Sagal scan.

61:17

For all those of you who have these questions and,

61:19

and would like a little bit more definition, um,

61:22

I did create a Cy nasal mastery course.

61:26

It's, uh, between two

61:27

and three hours gets into more of the

61:31

inflammatory disease and the sinusitis

61:34

and the O osteo mato complex, et cetera, with examples

61:38

of all these different types of cells, the, you know,

61:40

the hower cell, which is the max ethmoidal cell

61:43

below the, the orbit.

61:44

Um, and, and the named cells so to speak,

61:48

and how to distinguish them.

61:50

Most of the time the surgeons nowadays are doing a

61:55

relatively minimalistic surgery.

61:57

They're just trying to open the osteo natal unit.

62:00

So the ATE process is taken down

62:03

that allows the infundibulum

62:05

and middle medias to drain more easily.

62:08

Sometimes they're doing the partial ethmoidectomy,

62:11

not all the time, um,

62:14

and they're just trying to open the channels.

62:17

Same thing with the frontal ethmoidal recess.

62:19

They're just trying to open that up for frontal sinus

62:21

so it will drain properly

62:22

because the more what they found is the more they operate

62:25

and the more they take out the, the

62:28

more likely you've screwed up the muco ciliary clearance

62:32

that normally pushes the mucus in the appropriate location

62:38

back in the back of the throat.

62:40

And then we go and we swallow it down.

62:45

So that's actually the best way, you know, the natural way

62:48

that mucociliary clearance goes.

62:50

It, it passes it back to the pharynx for us

62:52

to throat to swallow it down.

62:54

If you do too much of this operation, you ruin all the Celia

62:57

and everything, then it's all distorted

62:59

and you have chronic sinusitis

63:00

because it's not draining properly.

63:02

So a little bit more minimalistic about functional

63:05

endoscopic sinus surgery these days.

63:08

Uh, please can you explain exactly what we have to look

63:10

for anterior ethmoidal artery in our report,

63:12

so I don't even report on the anterior ethmoidal artery.

63:15

Anyone who's doing sinus surgery endoscopically should be

63:19

able to identify the anterior ETH

63:22

and posterior ethmoidal air, um, communications.

63:26

Um, it's that little triangular thing that you see.

63:29

Again, I did describe this in my mastery series.

63:32

Of course, it's the little triangular opening to the, uh,

63:37

to the f to the moid air cells, um,

63:40

that you'll see on the coronal CT scan.

63:44

That is the potential source

63:46

of an orbital hematoma if they nail it.

63:49

But orbital hematomas are incredibly uncommon nowadays

63:53

with endoscopic sinus surgery.

63:55

Everyone knows the anatomy.

63:57

They do 3D to guide them most often,

64:01

and so they know where the carotid artery is,

64:03

the up optic nerve, the anterior ethmoidal art artery.

64:06

So it's pretty rare to, to nail that.

64:09

Uh, please, you have to. Okay. Uh, question number two.

64:13

What was question number two?

64:15

Uh, Dr you said that was about pop puffy tumor.

64:19

Oh, pop puffy tumor. So pop puffy tumor, as you saw in

64:21

that specific case, you saw a defect

64:24

that was in the frontal sinus leading to the scalp

64:27

and it was a large inflammatory process, not a tumor

64:31

that occurs in the scalp

64:33

and then presents as a soft tissue mass

64:36

in the frontal region

64:37

and most commonly from frontal sinusitis.

64:40

When you have pot puffy tumor, you always have

64:42

to worry about potential intracranial complications,

64:45

which would include a meningitis, a sinus thrombosis,

64:48

and an epidural abscess.

64:54

I think that's it. Dr. uim? Yeah, I think so.

64:58

Well, thank you so much for the case review

64:59

and for answering all those questions you got.

65:01

We appreciate it.

65:03

My pleasure. Any other announcements?

65:07

Yes, this is also the official kickoff

65:09

of our new webinar series Case Crunch Rapid Review,

65:13

which are one hour rapid fire case reviews taking place

65:16

between February and April.

65:18

So if you're studying for the boards

65:20

or you like case reviews like this, you can register

65:22

for this series at the link provided in the chat.

65:25

Hope to see you at those case reviews.

65:29

Be sure to join us next week on Thursday,

65:31

February 29th at 12:00 PM Eastern, where Dr.

65:34

Elizabeth Arle will deliver a lectured entitled in

65:37

preparation for Women's History Month screening

65:40

Mammography Saves Lives.

65:42

This lecture is co-sponsored with A A WR

65:45

and you can register for that@mrionline.com

65:48

and follow us on social media

65:49

for updates on future NOOM conferences.

65:52

Thanks again. Thank you Dr. Sso.

65:54

Thank you everyone for attending and have a great day.

65:57

Thank you. You too.