SCCA of the Larynx: What Radiologists Need to Know, Dr. Suresh Mukherji (2-8-24)
HIDEInteractive Transcript
0:02
Hello and welcome to Noon Conference, hosted by MRI Online
0:06
Noon Conference connects the global radiology community
0:09
through free live educational webinars that are accessible
0:12
for all and is an opportunity
0:14
to learn alongside top radiologists from around the world.
0:17
We encourage you to ask questions
0:19
and share ideas to help the community learn and grow.
0:22
You can access the recording of today's conference
0:24
and previous new conferences
0:26
by creating a free MRI online account.
0:28
Today we're honored to welcome Dr.
0:30
Resh McCury for a lectured entitled SCCA of the Larynx.
0:34
What radiologists need to know, Dr.
0:37
McCury currently holds academic appointments at numerous
0:39
institutions and currently serves as the National Director
0:42
of Head and Neck Radiology at ProScan Imaging
0:45
and Regional Medical Director at
0:46
Envision Physician Services.
0:48
His primary scientific interests have focused on
0:51
investigating emerging metabolic physiologic imaging
0:54
techniques to evaluate head and neck cancer
0:58
and to differentiate recurrent tumors
1:00
from post therapeutic changes.
1:02
Dr. McCury is a devoted educator
1:04
and has been an invited speaker on over 500 occasions.
1:07
We're grateful to him for his support of MRI online
1:09
and for serving as our head and neck neuroradiology advisor.
1:13
At the end of the lecture, please join him in a q
1:15
and a session where he'll address questions you may
1:17
have on today's topic.
1:19
Please remember to use the q
1:20
and a feature to submit your questions so we can get to
1:23
as many as we can before our time is up.
1:25
With that, we're ready to begin today's lecture. Dr.
1:28
McCorey, please take it from here.
1:31
Hey, thanks a lot f uh, again for having me.
1:33
Um, and then also, you know,
1:35
I'll take my glasses off real quick.
1:37
I just wanna thank the audience, um, for taking the time to,
1:41
uh, attend this talk, but also thank the modality people.
1:45
I think for the people that are joining, you know,
1:47
I've been working with Modality now for, I think it's,
1:50
I think four years, four or five years right now.
1:53
Um, and I can say with full honesty
1:58
and, and passion and pleasure,
1:59
they really are just a terrific team.
2:01
So for those of you that haven't joined Medal yet,
2:04
I certainly would encourage you because I think it is now.
2:07
I think we've eclipsed all of their platforms
2:09
and we are the, the largest educational
2:12
platform in the world right now.
2:13
And I think it's not only due to the content,
2:16
but really for the terrific people
2:18
and the culture and modality.
2:19
So, um, Ashley and everybody else, you know, thanks so much.
2:22
Um, and like I said, all of you that are joining up,
2:24
you know, please, please come and check it out.
2:27
So, what I'm gonna be doing over the next, um, 45 minutes
2:32
to 50 minutes is I'm gonna be talking about anatomy
2:35
and pathology at the larynx.
2:37
I'm specifically gonna talk about what the surgeon needs
2:39
to know, but I can change this to
2:41
what the Radiat radiation oncologist needs to know
2:44
and the medical oncologist needs to know.
2:46
And again, one of the things I'm really grateful for,
2:49
for Modality and having these seminars is
2:52
that I have a full, you know, hour with you
2:54
and I, as I mentioned, Ashley, I actually did block off, uh,
2:58
time after I get done if we want
3:00
to have a robust q and a session.
3:03
Um, I know we have people from all around the world.
3:05
I know there's some people maybe in the middle of the night
3:07
that have logged on live as well too.
3:09
And so, you know, if you're gonna make the effort to do
3:12
that, I wanna make sure that I make the
3:13
effort to be available to you.
3:14
So I think that's one of number one, one of the real values
3:17
of having a true exchange.
3:19
So if you have any questions at the end of it, you know,
3:22
don't hesitate to ask.
3:23
I I, I blocked off another 25 to 30 minutes.
3:26
Um, so I'm here for you.
3:28
The second thing is, you know, you go to a lot of meetings
3:31
and basically a lot of these meetings right now, you are,
3:36
as lecturers, were asked to give talks in 15 to 20 minutes.
3:40
And what I've noticed over the last 30 years
3:43
that I've been doing this is that in that time,
3:45
you're pressed just to get through the material.
3:47
And I think part of the teaching aspect is, has been lost.
3:51
So that's why I'm really grateful too, to have this time.
3:53
So what I really want to be able to do, my real goal
3:56
for this is I wanna make you guys learn it.
3:58
So whoever's on this talk, if,
4:00
if you don't understand the anatomy, the larynx,
4:02
and you don't understand sort of the key elements
4:05
that you should include your report,
4:07
it's not on you, it's on me.
4:08
So, you know, I want to take full responsibility
4:12
for trying to teach you this stuff.
4:14
And again, I'm thankful for, for you joining me
4:16
and also Modality and,
4:18
and Ashley specifically for,
4:20
for all of, for all of her help.
4:22
So the first thing that we do is
4:24
that when we talk about laryngeal imaging,
4:26
at least in the United States,
4:28
and I think this is mostly around the world, the majority
4:31
of the laryngeal imaging that we'll do is actually with ct.
4:35
Now, there are some places that do MR as well.
4:38
You know, I've always grown up using
4:40
CT for a couple reasons.
4:41
Number one, especially with multi detector imaging.
4:44
And I have 64 slice here that's probably old, you know,
4:46
you can get up to three 20 or, um, now
4:49
with photon counting ct, I mean it's, it,
4:51
the resolution's incredible.
4:53
But if the, the key thing is, is that
4:56
because now with multi detector imaging, it's
4:58
so quick to acquire the images.
5:01
If I look at a hundred cases,
5:03
if I look at a hundred patients with head
5:04
and neck cancer, especially with laryngeal carcinoma,
5:07
I know I'm gonna have a higher percentage of patients
5:10
that are not going
5:11
to have motion artifact if I do CT versus if I did,
5:15
Mr MR gives you exquisite imaging, certainly.
5:19
But on the other hand, when you are dealing with patients
5:21
with laryngeal carcinomas, they're oftentimes, uh,
5:24
drinkers, they're smoking too.
5:25
And they may have emphysema
5:27
and they may not be able to lay on their back as long.
5:30
So that's why I tend to use more CT and mr
5:32
and I think that's pretty much reflective
5:34
of practices around the world.
5:36
Um, we always have
5:38
to now acquire in seven millimeter thick section.
5:41
So, you know, I have 0.625 here.
5:43
You know, you can do that to 0.5,
5:46
but I think now with the prevalence
5:48
and dissemination of the technology
5:50
of multi detector imaging,
5:51
you really shouldn't be acquiring
5:52
greater than one millimeter.
5:54
'cause I think it's just easier to do.
5:56
Always remember to do the overlaps. In this case.
5:59
We look at our images about approximately 1.25 millimeters
6:03
with some overlap, and we'll see
6:05
obviously why that's important.
6:07
We always give intravenous contrast.
6:09
And what I end up doing, what, what I tend to do is to, um,
6:14
see, uh, to give contrast in hand.
6:17
So I'll give 75, uh, ccs in general.
6:20
In total, we tend to use a loading dose.
6:23
So we'll give 50 ccs initially in order to, to in,
6:28
in order to give the contrast enough time
6:30
to seep into the soft tissues
6:31
and the tumors, unfortunately,
6:33
I was late raised in the last century,
6:35
and so I remember when multi detector imaging first came out
6:39
and people were just basically giving contrast
6:42
and injecting, and inadvertently people were getting CT
6:45
anies without even knowing it.
6:47
So that's why we use this dual phase technique
6:49
where we give 50 ccs, we wait for about 90 seconds,
6:52
that allows the contrast to go into the soft tissues,
6:55
and then we give another 25 or 30 ccs, and then we acquire.
6:59
So that's what we mean by the dual face technique.
7:02
And one of the biggest pitfalls that, that I've seen, um,
7:06
in laryngeal imaging is, is it's just better
7:10
to do this cts in quiet respiration.
7:13
And when we start looking at early phase laryngeal
7:16
carcinomas, you'll see why,
7:17
because if you just do it in quiet respiration,
7:20
I think you see in my hands the vocal cord separate.
7:23
But oftentimes what I see is
7:25
that the technologists are asking
7:26
the patients to hold their breath.
7:27
And if you do the do that, it closes the vocal cord.
7:30
So you really can't see the vocal fos.
7:33
So the reason why that started is, again,
7:36
this is back in the old days when I was a resident,
7:38
we would do and as a fellow, is
7:41
that it took us about 30 seconds to do a single,
7:43
single acquisition for one slice.
7:46
And so as a result, the patients would, would move if we,
7:50
if we didn't tell them specifically to hold their breath.
7:53
'cause if they just breath normally
7:55
that would result in motion artifact.
7:57
So that's why we, it was, we would say, hold your breath
8:00
so it wouldn't move, unfortunately.
8:02
Now we don't need to do that.
8:04
And if you do hold your breath, you're, you are unable
8:07
to see lesions involving the medial portions
8:10
of the true VCA ports.
8:11
So please, please, please just do your CT scans in
8:15
quiet respiration.
8:16
Please don't do them with some type of breath hold
8:19
because you do, you're just not gonna see, you know, all,
8:22
all of the, all of that anatomy in the spread patterns.
8:26
So when we, excuse me, when we look at the larynx,
8:29
the larynx is actually divided into three areas.
8:32
And we're gonna go over this in, in detail, like I said,
8:35
just because, you know, we have some time to do it.
8:38
So the larynx is divided into a supraglottic larynx,
8:41
and the glottic is the other term for true vocal cords.
8:44
Then we have a glottic larynx,
8:46
which is the true vocal chords.
8:47
And then we have this area that's
8:49
below the true vocal chords,
8:51
which is the sub glottic larynx.
8:54
When we talk about, about the supraglottic larynx,
8:56
and again, that larynx is gonna be
8:58
above the true vocal cords.
8:59
There are four primary components
9:02
of the supraglottic larynx,
9:03
and we're gonna go over this in
9:04
detail, so don't worry at all.
9:06
You've got the epiglottis,
9:08
which is it's anterior midline structure.
9:10
Then you have a fold of tissue
9:12
that is running from the retinoid cartilages
9:15
to the epiglottis.
9:16
This is the area epiglottic fold.
9:19
Then we have the false focal cord,
9:21
and then we have the laryngeal ventricle.
9:23
So these are the four components of the supraglottic larynx.
9:26
And like I said, you know, just,
9:27
just don't worry about we're,
9:28
we're gonna go over all of this.
9:32
Now, I remember back when I was, again, I, I always talk
9:35
because I'm old enough to say this right now, I back,
9:38
I remember back when I was a resident and a and,
9:40
and a fellow, and I did a two year neuro fellowship,
9:44
and my focus obviously was on head and neck.
9:47
And I remember, uh, my first year I sort
9:49
of learned temple bone, but even when I started the second
9:52
year, I was completely confused on the larynx.
9:55
I just could not get it
9:56
because as soon as I would start talking about the larynx,
9:59
I had all these multisyllabic terms, like, hi,
10:03
epiglottic membrane area, epiglottic, fo thyroid,
10:06
hyoid membrane, hypothyroid ligament, thyroid muscle.
10:10
And the next thing I knew,
10:11
I was just completely lost in the word salad.
10:14
It was incredibly confusing to me.
10:17
So I'm not the sharpest tool in the shed,
10:20
but at some point, you know, my little 20
10:22
or 30 watt light bulb went off
10:24
and I realized, hey, um, all of these multi-syllabic terms,
10:29
they're really based on the five primary
10:33
components of the larynx.
10:35
And what I mean the primary components, I mean, what I kind
10:38
of referred to as the big five.
10:39
So I dunno if you've ever been on a safari,
10:41
but you know, basically on every safari has the
10:43
big five animal.
10:44
So you've got an elephant, a lion, a rhino, a water buffalo,
10:48
and a and a cheetah.
10:50
They're easily recognizable.
10:52
And so if you sort of take that same concept and,
10:55
and you look at the larynx,
10:56
you realize there are really only five main
10:59
components of that larynx.
11:01
And so what I mean by this is what I did is I spent the,
11:04
the next two weeks
11:07
just memorizing the five main scaffolding
11:10
and the five main components of the laryn.
11:11
So you've got the hyoid bone here,
11:14
then you've got this cartilage right here,
11:16
which is the thyroid cartilage.
11:17
So what do you call the membrane
11:19
that runs from the thyroid cartilage to the hyoid bone?
11:21
Well, that's the thyroid hyoid membrane.
11:23
Then you've got this little structure right here,
11:26
which is the epiglottis.
11:27
The epiglottis is anterior and midline.
11:29
So what do you call this ligament
11:31
that goes from the hyoid bone to the epiglottis?
11:33
Well, it's a high, high epiglottic ligament.
11:36
That's a, that's a bunch of syllables.
11:38
I can't even count that eye.
11:39
I need an AI algorithm for that.
11:41
So if you go down here, you look at this cartilage,
11:43
which is the OID cartilage,
11:45
and then if you go down below it,
11:47
you have the cricoid cartilage.
11:48
So what do you call this junction between the cricoid
11:51
and the hyoid cartilage?
11:53
Well, that's the cricoarytenoid joint.
11:55
If you, there's a muscle
11:57
that goes from the thyroid cartilage that goes
11:59
to the hyoid cartilage.
12:00
What do you call that? Muscle hyoid muscle.
12:04
If you look real closely,
12:05
there's a little ligament light right here
12:07
that goes from the thyroid cartilage to the epiglottis.
12:10
Well, what do you call that ligament?
12:12
That's the thyroid epiglottic ligament.
12:14
So again, now we're getting to about 10 or 12 syllables.
12:17
Here's a ligament right here
12:19
that runs from the crico cartilage to the thyroid cartilage.
12:22
What do you call this ligament?
12:23
Well, that's just the cricothyroid ligament.
12:26
So you see where I'm going with this?
12:28
All of these different ligaments in all
12:30
of the different muscles derive their name from these five
12:34
primary components.
12:36
So once I kind of realized that, what I ended up doing,
12:39
and I would encourage you to do this too, is just
12:42
for the next two weeks, just
12:44
before you go to bed, you know, um, you know,
12:48
just look at a image like this
12:51
and just say, what are those five things?
12:52
I've got the hyoid, I've got the thyroid,
12:55
I've got the epiglottis, I've got the cricoid,
12:58
and I've got the retinoid.
12:59
All of a sudden, the big five right here, I would argue,
13:02
is gonna be as recognizable as the big five
13:05
that you'd see on your safari.
13:08
Now if you look real close, just for grins,
13:10
so this is the OID cartilage,
13:12
and there's a little tiny cartilage right here.
13:14
This is my favorite cartilage of the whole body, you know,
13:17
'cause when I look at that, if you look at it, it sort
13:19
of looks like this, it sort
13:20
of looks like the Harry Potter sorting hat.
13:22
So I was just telling Universal Studio Studios the other
13:26
day, and I was able to go to the Harry Potter exhibit,
13:29
and I'm like, yeah, that just looks like that sorting hat.
13:32
So if you wanna learn a six little cartilage right here,
13:34
just for grins, that's called a corniculate cartilage.
13:37
And if you've ever watched Harry Potter,
13:38
you can always remember it now
13:39
because of that little sorting hat.
13:43
So as I mentioned
13:44
before, when you are starting to look at the, uh, larynx,
13:48
always do axial images
13:50
and always do the sagittal and the coronal images.
13:52
And, you know, I've gotta admit, I trained in the days
13:54
of axial images.
13:56
I, I don't find these as helpful probably as I should, just
13:58
because I spent the first 25 years of my life doing my own,
14:02
uh, reconstructions in my own brain.
14:04
But certainly it is routine right now
14:07
and essential that you always reconstruct your laryngeal
14:11
images into sagittal and coronal planes.
14:14
And I know I, I sometimes read out with people, uh,
14:17
globally, and, uh, sometimes that's not done routinely.
14:20
So if you're not doing 'em, you know, please talk
14:22
to your technologist because they really can be
14:25
done instantaneously.
14:28
So the next thing that we'll talk about is
14:31
that when we talk about the, the larynx
14:34
and especially laryngeal tumors,
14:37
it really have a very nonspecific appearance to this.
14:40
So for instance, this is an example
14:42
of squamous cell carcinoma involving the larynx.
14:45
And this is at the level of the false focal chords.
14:47
And we'll come back to this,
14:48
but if you see the tip of the retinoids,
14:50
it's a false vocal cords.
14:51
Now don't worry about that, I'm just introducing it now
14:54
as a radiological landmark, but we'll come back to it.
14:57
But the point is that this is squamous cell carcinoma.
15:00
Here's an example of another tumor involving the larynx.
15:03
Looks very, very much like the squamous cell.
15:05
This was actually minor salivary gland carcinoma.
15:08
And this example was actually tuberculosis.
15:11
So the first point that I wanna make is that the majority
15:14
of the tumors, and even the majority of the pathology
15:17
that you'll end up seeing in the larynx is
15:19
oftentimes non-specific.
15:21
Now, this talk is primarily gonna be focused on neoplasms.
15:25
Maybe one day in the future we can cover all the pathology,
15:28
uh, in the larynx.
15:29
But right now we're gonna focus on neoplasms.
15:31
But the point that I wanna make is, is that
15:34
the neoplasms have a really non-specific appearance to it.
15:39
And the concept that I wanna drill home is that as many
15:43
of you know, um, you know,
15:44
I see patients in clinic every Wednesday afternoon.
15:47
So yesterday I was actually in ENT clinic for three
15:49
to four hours, uh, examining the patients,
15:53
watching their endoscopies and going over their images.
15:55
And it really drills home the point
15:57
that when you are looking at lesions involving the larynx,
16:00
the surgeons are easily gonna be able
16:01
to take an endoscope down here.
16:04
So yes, you can sort
16:05
of give the standard differential diagnosis,
16:08
but the fact of the matter is they can see this,
16:10
they can biopsy, it goes to the pathologist
16:13
as we'll see later.
16:14
Our main goal is not necessarily to give a laundry list,
16:18
it's really to help identify spread patterns.
16:20
And again, we'll talk about that later.
16:23
Occasionally, you can make specific diagnosis.
16:26
This is an enhancing mass involving the lateral aspect
16:30
of the sub glottic larynx.
16:31
This was a little sub glottic hemangioma, thanks
16:34
to Varsha of Joshi.
16:35
She's now, I think, president of Indian Society
16:37
of Head and Neck Radiology.
16:38
She was my, uh, fellow many years ago.
16:40
Um, thank you for her.
16:41
For this example, here's an example
16:44
of a densely enhancing mass involving the
16:48
true vocal cords.
16:49
You can see the tubular enhancement very similar
16:53
to the artery in the vein.
16:54
This was an arter venous malformation.
16:56
And in this case, this was a lesion arising from
16:59
the crico cartilage.
17:00
This is one of the more common lesions
17:04
that arise from the cartilages to involve the larynx.
17:06
And this in fact was a chondra sarcoma.
17:08
So based on this, occasionally you can come up
17:11
with a specific histologic diagnosis.
17:14
But the point is, is that these tend to be,
17:16
um, very, very rare.
17:18
Oh, excuse me, very rare. And it's not, it's not common.
17:23
So let's talk about the normal anatomy of the larynx.
17:26
So what we're gonna do is that we're gonna start
17:28
with the supraglottic larynx.
17:30
And we're first gonna talk about the epiglottis.
17:32
So this is where we're gonna go to that, that,
17:34
that wonderful anatomy.
17:36
So what you see here is the sagal image right here
17:39
involving the, the larynx.
17:41
And this line tells you exactly where we are.
17:44
So we have this red line right here,
17:46
and it's going through the larynx.
17:48
And if we look anteriorly, this is
17:50
what our surgeon see endoscopically.
17:52
So the epiglottis remember is an anterior midline structure.
17:56
So when you perform endoscopy, you can see
17:58
that epiglottis anteriorly.
18:01
So we know the epiglottis is anterior midline.
18:03
So when we perform a CT or an mr, in this case, it's an mr.
18:08
The epiglottis is located anterior midline.
18:10
Those are our radiological landmarks.
18:13
If you look anteriorly,
18:14
we can see these two little air pockets.
18:17
This is one of the vs.
18:18
The vs can be confusing in the larynx.
18:21
This is actually the vallecula.
18:23
So the ve are these little airbags
18:25
or these little sacs sacs
18:28
that are located at the superior portion of the larynx.
18:32
And this little fold right here is called the median
18:35
gloss epiglottic fold.
18:36
So this actually attaches to the back of the tongue base.
18:39
So we're sort of in this area right here.
18:41
This is where that, that this specific image is.
18:44
So here's our ula. There's one ula, there's two ula.
18:48
There's our media gloss of epiglottic fold.
18:50
But the key thing here is that epiglottis is midline.
18:53
Now here's an example of a tumor
18:56
that's involving the epiglottis.
18:58
It's located anterior midline.
19:00
So this is what we see at endoscopy,
19:02
and this is what we see on a CT scan.
19:05
So how do we know that this is involved in the epiglottis?
19:08
Because again, excuse me, it's anterior and midline.
19:13
Remember the anatomy is constant.
19:15
So very important you understand this
19:17
because now what we're gonna do
19:18
is we're gonna talk about the next location
19:21
of the supraglottic larynx.
19:23
So this is called the airy epiglottic fold.
19:27
So remember when I showed the retinoid cartilages,
19:29
the retinoid cartilage were, were paired cartilages
19:32
that were off the midline.
19:34
So what do you call this fold of tissue
19:36
that runs from the retinoid cartilage all the way
19:39
up to the epiglottis.
19:40
Well those are the area epiglottic folds.
19:43
So this was our epiglottis here anteriorly.
19:46
And this fold of tissue, excuse me,
19:49
located right here on the right
19:50
and on the left, these are the area epiglottic folds.
19:54
So the area epiglottic folds are paired midline structures.
19:57
So when we look at this, uh,
19:59
this T one weighted mr right here,
20:02
this is one area epiglottic fold on the right.
20:04
Here's the other area, epiglottic fold on the left.
20:07
This is our epiglottis. That's anterior midline.
20:11
This is a exophytic tumor involving the right
20:13
area epiglottic fold.
20:14
This is what our surgeons would see at endoscopy.
20:17
And this is what we see radiologically.
20:20
This is an area epiglottic fold carcinoma.
20:23
Now, one of the biggest questions I always get was,
20:26
you know, I look at this
20:27
and sometimes I see this asymmetry
20:30
in the area epiglottic folds.
20:32
And if you have looked at, at enough N ct, sometimes
20:35
as you know, paralyzed vocal cords can give you a thickened
20:39
right area epiglottic fold.
20:41
So the question comes up and,
20:42
and you're like, well, how do I know
20:44
that this is actually a tumor versus a paralyzed cord?
20:48
And the way that I do it is the following.
20:50
So first of all, both a paralyzed cord
20:53
and a tumor can result in, if you will,
20:56
asymmetrical thickening of the area epiglottic fold.
20:59
But if you look at this area right here,
21:02
this is the piriform sinus on the right side,
21:04
and this is the piriform sinus on the left side.
21:07
The classic para midline cord
21:11
of a paralyzed cord is going
21:13
to result in ipsilateral dilatation
21:16
of the ipsilateral piriform sinus.
21:19
But if you have a tumor, then
21:20
that's gonna result in narrowing
21:22
of the right piriform sinus.
21:24
So in this case, if you look at this
21:26
and you're a little confused, you know, look at
21:28
that piriform sinus.
21:29
I mean if you see that narrowed, that raises your suspicion
21:33
that you actually may be dealing with a tumor.
21:37
Regardless if you it it, it is completely okay.
21:39
If you're not sure and you're looking at the cts
21:42
and you see this thickening right here,
21:44
it's completely appropriate
21:46
to recommend an endoscopy if there's any question at all,
21:49
because again, you're not gonna be able
21:51
to see mucosal tumors.
21:52
But the point here is that,
21:54
just remember this is the normal area epiglottic fold
21:56
because it's pyramid line.
21:58
This area epiglottic fold is shows a mask
22:02
and the resulting narrowing
22:04
of the piriform sinus all put together
22:07
indicate a primary site involving the right
22:09
area epiglottic fold.
22:12
Now I just mentioned the area epiglottic fold here on the
22:15
right and on the left.
22:16
Now the piriform sinus is not part of the larynx,
22:20
but I did wanna mention this here
22:22
because the area epiglottic fold is here.
22:25
And I mentioned the last slide is
22:26
that this space right here, just lateral
22:29
to the area epiglottic fold is the piriform sinus.
22:33
So if I go back again
22:34
before, here's one piriform sinus,
22:36
there's the other piriform sinus.
22:38
And the piriform sinus is technically part
22:41
of the hypo pharynx.
22:43
And piriform sinus gets its name from a pear shaped.
22:46
So when you actually look at a pear, you know,
22:49
normally this is the great part of the pear.
22:51
It's nice and juicy and chunky.
22:52
You know, I like a nice right pear, right?
22:54
So this is where you love to bite into.
22:56
Well when you look at the piriform sinus, the entrance
22:59
of this piriform sinus is the big chunky part of the pair.
23:03
And as you get lower
23:04
and lower into the piriform sinus, it reaches an apex
23:08
of the piriform sinus.
23:10
So when you are looking at your endoscopy,
23:12
here's the epiglottis here,
23:13
here's the area epiglottic fold on the right,
23:15
here's the area epiglottic fold on the left.
23:18
And this is the opening
23:19
or the introitus of the piriform sinus.
23:22
So when we look at this, uh, pet MRI scan,
23:24
there's one piriform sinus here on the right
23:27
and there's another piriform sinus here on the left.
23:30
So this is the mid portion of the pair.
23:32
And then when you get to the bottom of the pair, the apex,
23:35
well lo and behold, here's the apex of the piriform sinus.
23:39
And as you can see it's at the level
23:41
of the cricoarytenoid joint.
23:43
And we'll talk about this later.
23:45
But the point is, is that just realize this apex
23:47
of the pear is right here.
23:49
So this is not part of the larynx, it's part
23:51
of the hypo pharynx, but it's in very close app, uh,
23:54
proximity to the larynx.
23:57
So this is a normal area epiglottic fold.
23:59
On the left side, this is the piriform sinus,
24:03
and here we have a tumor
24:04
that's involving the piriform sinus.
24:07
There's a little bit of thickening here
24:08
of the area, epiglottic fold.
24:10
But notice how the majority
24:11
of this is in the piriform sinus.
24:14
And this just happens to be a pet,
24:16
A pet CT demonstrating abnormal uptake in
24:19
that piriform sinus.
24:22
So now we'll get back to the main components of the larynx.
24:25
And technically this is conceptually
24:28
for me the hardest one to identify.
24:30
This is referred to as the false VCAL cord.
24:34
So there's a false vocal cord,
24:35
and there's a true vocal cord.
24:37
So what exactly is the false vocal cord?
24:40
Well, if I go back, one slide,
24:44
a false VCA cord is this little fold of tissue
24:48
that's located just above the true VCAL cord.
24:50
So this is the area epiglottic fold.
24:52
And this fold of tissue right here is the false VCA cord.
24:56
The posterior portion of the false VCA cord attaches
25:01
to the top of the hyoid cartilage.
25:04
So the false VCAL cord attaches to the top
25:07
of the retinoid cartilage.
25:09
So when we talk about radiological landmarks,
25:12
where is the false VCAL cord?
25:14
The false focal cords attaching to the top
25:17
of the retinoid cartilage.
25:19
And if you will, the false focal cord is basically the
25:22
inferior reflection of the area epiglottic fold.
25:25
So when I look at this non-contrast, T one weighted Mr
25:29
what tells me we're at the false focal cord.
25:31
Well, you can see the top of one retinoid cartilage here
25:34
and the top of the ri other hyoid cartilage here.
25:37
That's our radiological landmark.
25:40
And this is an example of a false vocal cord tumor.
25:44
Here's the tumor right here.
25:45
It's actually involved in the opposite side as well.
25:48
But notice the yellow arrow right here points
25:51
at the cartilage.
25:52
That is just the hyoid cartilage.
25:54
So when we see this, we know we're at the false focal cord.
25:58
So on this coronal image,
26:00
here's a coronal image of the airway.
26:03
This red line tells us where we are.
26:05
So this is where we are here, this is where we are here.
26:08
When we were looking at the larynx, notice the top
26:10
of the roid cartilage.
26:12
And then right below it is the laryngeal ventricle.
26:15
This is the other V.
26:16
You have a vallecula and you have a ventricle.
26:19
It can be confused.
26:21
Remember the ve ula are the little saddle bags up at the
26:24
top of the larynx.
26:26
The ventricles separate the false focal cord from
26:30
the true vocal cord.
26:31
So if the way I look at it, it kind
26:33
of looks like a Yoda to me.
26:35
I hope you like the Yoda here,
26:36
but that's just the way I think.
26:37
So there's this air right here.
26:39
Look at the Yoda and look at the ears.
26:42
So when I look at the Yoder here,
26:43
the false focal cord is basically gonna be
26:46
at the top of the ears.
26:48
And then the ears are basically going
26:50
to be the air in the laryngeal ventricle.
26:53
So if we go from the false cord,
26:55
now we jump across the laryngeal ventricle
26:58
and now we're at the true cord.
27:00
Then look what happened to the ears.
27:01
Now we're below the ears of the Yoda.
27:03
So we jumped from the false focal cord
27:05
to the laryngeal ventricle through to the true vocal cord.
27:09
And on this anatomic illustration, now we're at the level
27:13
of the crico retinoid joint.
27:14
So I'll just go back one, there's a false focal cord.
27:17
Notice the top of the retinoid cartilage.
27:19
Look where this line goes.
27:21
Now we're at the Crico retinoid joint.
27:24
How do we know we're at the true vocal cords
27:26
because of the crico retinoid joint?
27:28
There's a crico cartilage here. Here's the OID cartilage.
27:32
That's our joint. If I go back one
27:34
that's the retinoid cartilage only.
27:37
Now the Crico OID joint tells us we're at the true VCO cord.
27:41
And here's a little illustration
27:42
of a true VCO cord carcinoma.
27:45
So when I look at the CT scan, this tells me
27:48
that there's a tumor right here.
27:50
The yellow arrow shows it.
27:52
Here's the Crico cartilage, here's the retinoid cartilage.
27:55
And I don't know if the way that I remember this is I think
27:59
of a little smiley face.
28:00
You know, back when I grew up in the last century, we used
28:03
to have a circle looking that had a smiley face on.
28:06
And now we're all fancy. We call these emojis.
28:08
But if you remember the smiling emoji right here,
28:11
see this little smiling face,
28:12
the crico cartilage is smiling at you.
28:14
The lips are sort of turned in.
28:16
But if you can remember this smiley face right here,
28:19
and remember the crico retinoid joint,
28:21
you'll always remember the radiological landmarks
28:24
for the true vocal cord.
28:27
And then the last bit of anatomy.
28:29
So what have we done so far?
28:30
Just to level set so far
28:32
what we've done is we've talked about the anatomy,
28:34
the supraglottic larynx.
28:36
So that was the epiglottis, the area epiglottic fold,
28:39
the false focal cord and the laryngeal ventricle.
28:42
That was a supraglottic larynx.
28:44
Now we're gonna talk about the crico adenoid joint
28:47
that tells us where the true vocal cords are located.
28:50
And now what we're gonna do, supraglottic glottic.
28:53
And now we're gonna talk about the sub glottic larynx.
28:57
So the sub glottic larynx is pretty, it's pretty simple.
29:01
What the sub glottis larynx is, is that part
29:06
of the larynx that is defined by the crico cartilage.
29:10
Remember the crico cartilage, right?
29:12
That was the one big cartilage
29:14
that basically forms the foundation of the larynx.
29:17
It's one of the big five.
29:19
So this is an example here
29:21
of a tumor involving the subglottic larynx.
29:24
And you can see it's involved, it's within this component
29:27
of the cricoid cartilage.
29:28
On the coronal images. This was the area epiglottic fold.
29:32
This was the false focal cord.
29:34
This is the laryngeal ventricle.
29:35
This is the true focal cord.
29:37
And here we can see the shoulders in the beginning
29:40
of the subglottic larynx.
29:42
And with a leap of faith,
29:43
you can actually see one crico cartilage on the left.
29:46
And the other, there's the ring, if you will,
29:48
and that defines the subglottic larynx.
29:51
So how do we identify the subglottic larynx?
29:54
Well, we look for the ring of the cricoid cartilage.
29:57
Now the mucosa
29:58
around the crico cartilage is very, very thin.
30:02
So when I look at this, I think of this surprise emoji.
30:05
So unlike this emoji right here, which is sort of smiling,
30:08
'cause that gives us the crico OID joint.
30:11
When I see the surprised emoji
30:13
and I see all of this air right here, that's t adjacent
30:17
to the cricoid cartilage that I know, I'm at the level
30:20
of the subglottic larynx.
30:21
So that's how I remember that.
30:23
And this is an example here of a tumor
30:26
that's involved in the subglottic larynx.
30:28
And you can see it's narrowing this.
30:31
Now these patients oftentimes present with St Strider.
30:34
If you're looking at a child,
30:36
the classic subglottic pathology that would present
30:39
with stridor was cr, right?
30:41
Because it would narrow the subglottic larynx in a,
30:44
in a, in an adult.
30:45
The Crico cartilage is well-formed.
30:48
And these patients
30:49
that have primary subglottic carcinomas oftentimes present
30:52
with difficulty breathing and they can be striders.
30:56
And that's because of the narrowing of the airway.
30:59
So what we've done so far is
31:02
that we talked about the normal anatomy of the larynx,
31:05
and we just spent a good 20 minutes going over the
31:07
gory detailed of the larynx.
31:09
So I want all of you all to remember the larynx.
31:11
And if you don't, you know, go back to the modality website.
31:14
You know, listen to this talk and,
31:16
and you know, we've got plenty of time
31:17
to understand the larynx.
31:20
Now the next thing and
31:21
how I'm gonna end this talk is really talk about the
31:24
real value of imaging.
31:26
So as I mentioned before, the majority of the pathology
31:29
that can be seen in the larynx can be visualized
31:33
by direct endoscopy.
31:35
So really, you know, when you get into the higher levels
31:38
of head and neck radiology,
31:40
it's more than normal versus abnormal.
31:42
It's more than basically listing five
31:44
or 10 things that you may see on your imaging study.
31:47
But it's actually trying to identify spread patterns
31:51
and staging because that's where the real value
31:54
of imaging comes in.
31:55
So this was a, an older slide,
31:58
and I still like to show it just
31:59
because it makes a really, really important point, is
32:02
that if you have early stage lesions, like a T one lesion,
32:06
these are typically treated
32:07
with conventional radiation therapy.
32:10
But as you go from T one to T four higher stage diseases,
32:14
you can see that the options
32:17
for treatment are total laryngectomy with
32:19
or without radiation therapy, radiation care, the,
32:22
and chemotherapy or a combination of, of chemo,
32:25
radiation and surgery.
32:27
So the point is, is as the stage gets worse,
32:31
the treatment options become much more aggressive.
32:35
And the challenge is, and I've seen this
32:37
before when I'm in clinic, is
32:40
that you'll have these patients right here
32:42
that are presenting with these masses,
32:44
these masses involving the larynx.
32:46
And this was an endoscopic view.
32:48
Now, when the patient is actually in the clinic
32:51
and you perform your endoscopy, well look here,
32:54
this is the airway.
32:55
If you've ever tried, and I haven't tried this,
32:58
'cause I, I just watch, I don't do the endoscopies,
33:00
but if I try to put a tube deep to this
33:03
and try to figure out the full extent of the disease,
33:06
I could occlude the airway
33:07
and the patient could just crash right there
33:10
in the clinic itself.
33:12
So my point is, is that there are a lot of things
33:15
that we provide, provide on radiology
33:18
that cannot be seen clinically that directly affect
33:23
how these patients are staged and how they'll be,
33:26
and then how and how they'll be treated.
33:29
Now, I'm not a big fan of standardized reports, you know,
33:34
I think, I don't know what a standardized report is.
33:36
I'll ask 10 people what a standardized report is
33:39
and I'll get 10 different answers.
33:40
So I'm not advocating a standardized report.
33:45
The term that I like to use is key elements.
33:48
So when we are evaluating patients with laryngeal carcinoma,
33:52
you know, I will give my residents and my fellows
33:54
and my, you know, my colleagues full freedom to put
33:58
what you want in, you know, your your discussion,
34:02
your your observations, your your summaries,
34:05
and so on and so forth.
34:06
But what I would ask you to do somewhere is
34:09
to comment on these key elements
34:11
because these key elements, subglottic spread,
34:14
ex laryngeal spread, cartilage invasion,
34:18
trans glottic spread,
34:19
and involvement of the anterior commissure.
34:21
If you comment on these five things,
34:24
you will directly affect staging in many, many cases.
34:27
And oftentimes you won't even affect staging,
34:29
but you'll affect
34:30
how these patients are specifically treated.
34:33
So what I wanna do in the remaining time
34:36
is talk about these five key elements
34:38
and how you can assess this if you understand the anatomy
34:43
that we just reviewed.
34:45
So the first key element is whether
34:47
or not they're subglottic spread.
34:49
Well, what's subglottic spread?
34:52
Well, sub glottic spread is just a tumor
34:54
that it spreads inferiorly to involve the subglottic larynx.
34:59
So again, and to understand this, we have
35:02
to understand the anatomy.
35:04
So here's an example of a cancer
35:06
that's involving the true vocal cord.
35:08
Here's the cricoid cartilage, here's the retinoid cartilage.
35:11
And we can see this tumor right here involving the
35:14
right true vocal cord.
35:15
And it's extending right here to the anterior commissure.
35:19
So here's the anterior commissure,
35:20
we'll talk about that later.
35:22
This back here is the posterior commissure.
35:24
So here we have a tumor involving the right true vocal cord.
35:28
When we look more inferiorly,
35:30
notice we're not at the crico retinoid joint.
35:33
And now we're starting to see the back
35:35
of the cricoid cartilage.
35:37
So now we're actually at the subglottic level,
35:39
no retinoid cartilage.
35:41
So I know we're at the top of the subglottic larynx.
35:44
And when we see this, we can see tumor
35:46
that's located right here.
35:48
So this is an example of subglottic spread.
35:51
The tumor is involved in the true VCA cord,
35:53
but it spreads inferiorly to the level of sub glottis.
35:58
Another example here, a right true vocal cord carcinoma.
36:02
Look at the O right here.
36:03
This is that surprise emoji that we just talked about.
36:06
And the yellow arrow right here points at this tumor
36:09
involving the subglottic lx.
36:11
So we have to ask ourselves, there's subglottic spread,
36:15
but we have to ask that question.
36:17
Who cares? You know, why does it make a difference?
36:20
Well, it makes a difference for the following, is
36:23
that if we, as the radiologists say there's greater than six
36:27
millimeters of subglottic spread at most institutions,
36:30
if the patients wish to be treated with surgery,
36:33
they'll have to undergo a total laryngectomy.
36:36
Think of that, a total laryngectomy
36:38
just based on what we see.
36:40
Because at endoscopy, especially in the clinic, it's really,
36:44
really hard to look at that subglottic spread
36:46
by performing an endoscope, they have to take the patient
36:49
to the operating room, they have to do a rigid examination
36:53
and this type of assessment by us in the clinic,
36:57
because now if we say this,
36:59
these patients may not wanna go total laryngectomy,
37:02
but oftentimes they're treated
37:03
with chemotherapy and radiation therapy.
37:06
So although this doesn't necessarily affect staging,
37:09
it does definitely tell them that this patients are,
37:13
are probably going to have to be treated with chemo
37:16
and radiation if they want to have some native preservation
37:20
of their voice and, um, their swallowing.
37:24
So the next key element is transo spread.
37:27
So what exactly is transo spread?
37:30
Well, transo spread is when a tumor crosses the
37:34
laryngeal ventricle.
37:35
So, you know, I think they're on the call today.
37:37
I, I have the privilege of reading out
37:39
with the folks in Tanzania as, as part of at Muhas as part
37:43
of, uh, part
37:44
of my r the RS NA visiting professors program we've been
37:47
doing now for almost two years.
37:48
It's really, really a joy.
37:50
And I remember I first told them that this is the definition
37:53
of trans glottic spread.
37:55
And actually one of 'em said to me, well, Dr.
37:57
Mukherjee, you know, why is it Trans Glo?
37:59
Why isn't, shouldn't it be called trans ventricular spread?
38:03
And they're actually right. It's a hundred percent right.
38:06
So it's, we call it trans glottic spread.
38:09
But functionally is when this tumor crosses over the
38:12
laryngeal ventricle.
38:13
So it's really crossing the ventricle.
38:16
So how does this work?
38:17
Well, you have a tumor right here involving
38:19
the supraglottic larynx.
38:21
And this case, notice how the inferior portion
38:23
of this tumor is above the level of the false fo.
38:27
But in this case, notice how the inferior portion
38:30
of the tumor crosses the false focal cord.
38:33
It crosses the laryngeal ventricle
38:35
and it crosses the true vocal cord.
38:37
So this is transo, ie. Trans ventricular spread.
38:42
So why does that make a difference?
38:44
Well, it makes a difference in the surgical options.
38:47
So here's a tumor involving the larynx.
38:49
So let's, let's, let's do what we learned about.
38:51
So this, where is this tumor? It's located anterior midline.
38:56
So of course it's in the sag glottis.
38:58
But let's take it to the next level.
38:59
It's involving the epiglottis. Why?
39:01
Because it's anterior midline.
39:03
So this tumor's extending into the pre epiglottic space.
39:07
Now where was this CT scan obtained?
39:09
Well, here's the crico cartilage,
39:11
there's the retinoid cartilage,
39:12
this is the crico retinoid joint.
39:15
Notice how there's no tumor here.
39:17
So in this case, there's no crans glottic spread.
39:21
So these patients potentially could be treated
39:24
with a supraglottic laryngectomy
39:26
where they resect the epiglottis, the area epiglottic folds
39:29
and the false fooc cords.
39:31
But what about in this case?
39:33
Well, this was a case I saw 30 years ago.
39:35
Sometimes I like to show these old cases
39:37
'cause there's a nice story behind it.
39:39
This was a case again, anterior and midline.
39:42
It's an epiglottic carcinoma.
39:44
I remember the surgeon said to me, well I think that this,
39:47
this tumor ends above the true vocal cords
39:50
and I can resect this with a supraglottic laryngectomy,
39:53
you know, perform this type of surgery.
39:56
But on the other hand, when I looked at the true vocal
39:59
cords, I can see the cricoid cartilage,
40:01
I can see the adenoid cartilage.
40:03
And lo and behold, there was tumor right here
40:05
at the true vocal cords.
40:07
And I remember I said
40:09
to the surgeon at the time when we looked at the
40:11
ct, I said, you know, Dr.
40:12
So-and-so I don't think you're gonna be able
40:14
to do a supraglottic.
40:16
The tumors involved in the right true vocal cord, you know.
40:19
And he argued with me and said, well,
40:20
you're just a radiologist, you can't see this.
40:22
Well, they came back next week and said, ah, you were right.
40:24
They ended up had, uh, took the patient
40:26
to the operating room.
40:28
You know, they found this tumor
40:29
involved in the true VCA cord.
40:30
It had crossed the laryngeal ventricle.
40:32
So they were not able to do a supraglottic laryngectomy.
40:36
And in this particular case,
40:38
the only surgical option was a total laryngectomy.
40:42
So because we told them this, these patients were treated
40:45
with chemotherapy and radiation therapy.
40:48
So in these cases, not only do we affect the type
40:51
of surgery, but because chemo
40:53
and radiation is an accepted treatment.
40:55
Now for laryngeal carcinomas, we actually directly affect
40:59
how these patients are treated.
41:01
Another example here, you can also have
41:05
carcinoma start from the true vocal cord
41:07
and work its way up.
41:08
So before we were up here
41:10
and it came down, now we're down here at the true cord
41:14
and these things can extend superiorly.
41:16
So here's an example of a patient
41:18
that has a true vocal cord carcinoma.
41:21
Where are we right now? There's a cricoid cartilage.
41:24
There's the retinoid cartilage, it's smiling at us, right?
41:27
That's a true vocal cord carcinoma. Where are we at now?
41:31
Will we see one retinoid cartilage,
41:33
the other retinoid cartilage.
41:34
And notice how the paralytic fat or the para laryngeal fat
41:38
and the little bit of laryngeal ventricle here,
41:40
they look symmetric.
41:42
So there's no tumor at this level.
41:44
So this tumor is isolated to the true vocal cords
41:47
and they could perform this type of procedure,
41:49
which is a hemi laryngectomy.
41:52
But here's another example.
41:53
Here's a tumor involving the right true vocal cord.
41:56
And where are we now see this little top
41:58
of the oid cartilage right here?
42:00
This little muscle right here is the lateral
42:03
thi retinoid muscle.
42:04
See the tiger stripes here?
42:05
You can see dark, you can see black,
42:07
you can see dark, you can see black.
42:09
These are the nice stripes on the left.
42:12
And on the right hand side we can see tumor here involving
42:15
the right perilaryngeal space.
42:17
So this is an example of trans glottic spread.
42:21
Why is it important? Because the surgeons cannot perform.
42:24
Now this hemi laryngectomy, so I know in my is,
42:29
if I see this, the patients are oftentimes not
42:32
treated with surgery.
42:34
But again, in order to preserve native function,
42:37
these patients are oftentimes treated with chemotherapy
42:40
and radiation therapy purely
42:42
because of the spread that we detect.
42:44
And oftentimes the spread is submucosal.
42:47
They cannot see that act on their clinical imaging.
42:51
While transo spread was the hardest one to identify,
42:55
that was conceptually the hardest.
42:57
The other ones are, are much more straightforward.
43:01
So a T four lesion is ex laryngeal spread.
43:04
These are just kind of, uh, straightforward examples
43:07
of tumors that are involving the larynx
43:09
that spread into the soft tissues.
43:11
I think we can all make this diagnosis,
43:13
but just realize ex laryngeal spread is T four.
43:17
But on the other hand, these folks are obvious.
43:21
You know, what we wanna do is look for
43:23
that early ex laryngeal spread.
43:25
So earlier I showed you a case of piriform sinus carcinomas.
43:29
The piriform sinus carcinoma is lateral,
43:32
it's the piriform sinus is located very laterally
43:35
and sometimes these tumors can extend into the soft tissues
43:39
of the neck, oftentimes
43:40
through this little opening right here
43:42
for the superior laryngeal artery and nerve.
43:45
And if you look real closely, notice
43:47
how this piriform sinus cancer has grown out
43:51
into the space.
43:52
So here's a piriform sinus carcinoma on the right hand side.
43:56
Here's the normal vessels right here.
43:59
And look how the left hand side,
44:01
we can see the tumor right here is abutting these vessels
44:05
and displacing these vessels.
44:07
So this is an early example of ex laryngeal spread
44:11
that cannot be seen clinically,
44:13
but what we see radiologically
44:15
and upstages these tumors to a T four.
44:17
So that's early example of ex laryngeal spread.
44:23
The next key element for the larynx is cartilage invasion.
44:27
So the interesting thing about cartilage invasion, as many
44:30
of you know, I've been um, one
44:32
of the radiologists on the staging system since the fifth
44:35
edition and we're already to the eighth edition over time,
44:39
what we've done is that a T three lesion is defined
44:42
as erosion of the inner cortex.
44:44
And a T four lesion is defined by erosion
44:47
of the outer cortex of the thyroid cartilage.
44:50
So this is T three and this is T four.
44:53
In the old days, we would just wait for the larynx
44:55
to come back and the pathologist would end up making the
44:59
diagnosis and they would tell us where there was erosion
45:01
of the inner cortex or the outer cortex.
45:03
That's where this came from.
45:05
What's happened over the last, you know, 10 years
45:08
or so, 15 years or so is
45:11
because it's been accepted
45:13
that larynx cancers can be treated with chemotherapy
45:16
and radiation therapy.
45:17
As I've showed before,
45:19
these upfront decisions are made on base based on
45:22
what we say on imaging.
45:24
So I always like to say, you know, we in a way,
45:27
radiologists in a way are in a way at times the new
45:30
pathologist of the new millennium that
45:33
because of the acceptance of of imaging to detect erosion
45:37
of the interim, the outer cortex, this is now being used
45:41
to triage patients.
45:43
So here's an example of a tumor involving the larynx.
45:46
This is involving the anterior commissure
45:49
and this is an example of a T three lesion.
45:51
Notice the red arrow points at erosion of the inner cortex
45:55
and the outer cortex is maintained.
45:57
But here's an example of a T four lesion.
46:00
Notice how the erosion of the inner cortex
46:02
and the outer cortex are both eroded.
46:05
Now I often get asked
46:06
and I said, well how do you,
46:07
what do you do about these areas here?
46:09
Notice how there's absence of the cartilage.
46:12
Well, what I always do, at least in my practice,
46:15
I draw a line down the middle
46:16
and I compare one side to the other side.
46:19
Every one of us has ossification of the thyroid cartilage,
46:23
but each, each of us ossified a little bit differently.
46:26
But in general, the ossification tends to be symmetric.
46:29
So in this particular patient on the uninvolved side,
46:33
I can see right here this lamina of the thyroid cartilage.
46:36
I can see no uh, ossification and I see ossification.
46:40
So if th this area right here, I'm not very confident
46:44
that there's cartilage erosion.
46:46
But on the left hand side,
46:47
because that lamina is actually present
46:50
on the right hand side, the absence of this tells me
46:54
that there's a high likelihood of cartilage invasion
46:57
because in this patient the contralateral side was ossified.
47:00
So because this tumor is on the patient's right side,
47:03
this absence gives me a high degree of confidence
47:06
that there's cartilage erosion.
47:09
We can also look for cartilage erosion based on mr.
47:12
So either one of these is fine.
47:14
There's a lot of great work that was done,
47:16
especially dating back to the the 1990s.
47:19
And so you can perform mr, it's fine.
47:23
What you end up doing is that on the non-contrast T one,
47:27
this patient had a right-sided thyroid, uh, uh,
47:30
laryngeal carcinoma, the true VCA board.
47:32
What we do is we look for absence
47:34
of the fat in the right thyroid cartilage.
47:37
So notice the normal high signal thyroid cartilage on the
47:40
left, it's truncated on the right.
47:43
So this is evidence of cartilage evasion on uh,
47:46
cartilage erosion on mr.
47:49
You can also look for increased T two signal
47:52
or gadolinium enhancement.
47:53
All of these have been proven to be suggestive
47:56
of cartilage erosion.
47:57
But in general this is probably the one
47:59
that I most relied on.
48:01
It's the absence of fat involving the thyroid cartilage.
48:04
And this is just the pathologic correlation.
48:07
I want to thank uh, Supta aria from India
48:09
for giving me this nice example.
48:12
And then the last thing
48:13
that we'll talk about is anterior commissure.
48:15
So, so far the key elements are subglottic spread trans glo,
48:20
ex laryngeal spread cartilage invasion
48:24
and we will end with the anterior commissure.
48:28
So what is the anterior commissure?
48:30
Well the muscle that runs from the thyroid cartilage
48:33
or the retinoid cartilage is called the
48:35
thro retinoid muscle.
48:37
That is the vocalist muscle.
48:39
The most medial component of this is referred to
48:42
as the vitalis ligament.
48:44
Now this ligament attaches right here
48:47
to the inner peric conium of the thyroid cartilage.
48:51
There are three components or three little ligaments here
48:54
or three components that form this ligament that's referred
48:57
to as broils ligament.
48:59
So you have the ligament right here
49:01
that runs from the thyroid cartilage of the tip
49:03
of the epiglottis.
49:04
This is the thro epiglottic ligament.
49:07
The second component is that ligament
49:09
that I just talked about.
49:10
This is the voc callus ligament.
49:12
This is the medial thickening, the ligamentous portion
49:16
of the thro retinoid muscle and that's the voc ligament.
49:19
And the third component is the inner peronial.
49:23
So all of these three components form this thick area right
49:27
here, which is referred to as broils ligament.
49:30
And it's located at the anterior most aspect
49:33
of the larynx at the level of the true vocal cord.
49:36
And this is what's referred to as the anterior commissure.
49:41
So what ends up happening is the following is
49:44
that if you have a patient
49:45
that has a true vocal cord carcinoma
49:48
and it really extends anteriorly,
49:51
what are the surgical options?
49:52
Well from a surgical standpoint they're thinking hey, I need
49:56
to perform a total laryngectomy
49:59
or is it possible I could do some type of laser resection
50:03
and to remove that tumor
50:05
or should I treat these patients with chemotherapy
50:08
and radiation therapy?
50:09
Those are the decisions that are made.
50:12
So when you perform an endoscopy, the surgeons can go down
50:15
and they can end up seeing this.
50:17
So this yellow arrow points at a tumor involving the
50:20
anterior commissure.
50:22
Now when they see this
50:23
and they think it's pretty superficial, they may say, Hey,
50:26
this looks pretty good.
50:27
Maybe I can do a laser resection on this.
50:30
Um, some type of microdissection micro laryngectomy,
50:33
that's great, but what they cannot see
50:36
is this anterior extension.
50:38
They cannot see this extension anteriorly
50:40
and they oftentimes cannot see this extension
50:43
to involve the contralateral true cord.
50:46
It's really important about this anterior extension
50:49
because here's another example here.
50:51
This was a patient right here
50:53
that has an anterior commissure carcinoma.
50:55
This was originally staged as a T one lesion, but
50:59
but clinically, but when we looked radiologically,
51:02
look at this right here,
51:04
this is cartilage erosion right here
51:06
as this tumor extends anteriorly.
51:09
So some of these early stage T one lesions
51:13
that are not cured
51:14
by radiation therapy may be more aggressive,
51:17
but on the other hand, some are due to under staging.
51:21
So the clinical importance of this is that number one,
51:24
this tumor cannot be treated with micro laser resection
51:29
because of the cartilage erosion.
51:31
Number two, if we do detect the cartilage erosion,
51:34
it upstages to a T four.
51:36
So this patient cannot be treated
51:38
with radiation therapy alone.
51:40
The surgical option is gonna have
51:42
to be total ectomy at most institutions.
51:45
And if we see this, all of a sudden these patients have
51:48
to have chemotherapy and radiation therapy
51:50
because it's T four.
51:52
These are all sophisticated principles,
51:55
but on the other hand it all boils down
51:57
to you if you understand the anatomy
52:01
and you understand the crico retinoid joint.
52:03
Remember our smiley face right here.
52:05
You understand the anatomy of the anterior commissure
52:09
and now you can understand
52:10
how you can detect cartilage invasion.
52:13
These are simple concepts
52:14
and if you understand the anatomy,
52:16
you'll make a huge difference in
52:18
how your patients are treated.
52:21
So what we've done over the last 50 minutes
52:24
or so is that we went over the anatomy.
52:26
So remember the anatomy supraglottic larynx,
52:29
which is the epiglottis area, epiglottic fold, the uh,
52:33
false focal cord and the laryngeal ventricle we talked
52:36
to the true vocal cord was a crico OID joint
52:40
and the sub glottis was the base of the cricoid cartilage.
52:43
And then what we did is we talked about the five things.
52:46
These are the key elements to include in your report.
52:49
So you know, please try to comment on subglottic spread,
52:52
trans glottic spread, ex laryngeal spread cartilage invasion
52:56
and anterior commissure.
52:58
And so what I would ask you to do for the 400 plus people
53:01
that were on the call today is that for the next two weeks,
53:04
you know, just before you go to bed, just
53:07
identify the big five right here, hyoid, bone epiglottis,
53:11
thyroid cartilage or roid cartilage and cricoid cartilage.
53:14
If you just do this just for five minutes a day
53:17
for the next two weeks, you will understand the big five
53:20
and these cartilages will be as recognizable to you
53:24
as the big five safari, uh, animals
53:26
that we see on your right.
53:27
So thank you so much for your attention
53:29
and I'm happy to answer any questions.
53:32
Thanks so much for your lecture.
53:34
And yes, we are opening the floor for questions,
53:37
so if you have any, please place them in that q
53:39
and a feature.
53:42
And Dr. McCoury, if you can pop open that q and a box.
53:47
Yep, got it. Awesome.
53:51
Got quite a few in there already.
53:53
Yeah, sure. Yeah, no problem.
53:54
So the first thing, you're right at the,
53:56
the dual phase imaging,
53:57
I probably didn't do the best on that.
53:58
The dual phase imaging is, uh,
54:01
where we give a loading bolus.
54:03
So we give an initial arterial a bolus of about 50 ccs
54:07
and we wait so that early, uh, that dual bolus
54:12
we wait for about, uh, uh, uh, two minutes
54:15
or so that allows the contrast to go into the soft tissues
54:19
and then we give another bolus of about 25 ccs or so,
54:24
and then we acquire our images.
54:26
So that's the dual phase technique.
54:28
We described that in around 2005.
54:30
I think now, as you know, in many parts of the body,
54:33
you know, I think everything outside the head
54:35
and neck is an accessory organ.
54:36
I kind of joke about that, but I think if you live look at
54:38
the liver and the pancreas and and
54:40
and other organs, you know,
54:42
dual phase imaging is being used very commonly.
54:45
So that was the uh, definition for the, for the dual phase.
54:54
So do you want me to read off the questions
54:56
or do you wanna read 'em to me or how should we do this?
54:58
'cause there's stuff in the q and a
54:59
and there's stuff in the, in the chat, so, um,
55:02
Sure. Happy to read them to
55:03
you. Hopefully I don't
55:04
butcher too many of the words.
55:06
Okay, cool. Um, how do you, correct,
55:07
are you in q asy? Tric, are you
55:09
In Q or chat?
55:10
Are you in q and a or chat right now?
55:12
I'm in the q and a. Okay, perfect.
55:16
Yeah. How do you correct asymmetric position
55:18
and differ that from asymmetric thickening on larynx?
55:22
Yeah, that's a great question.
55:24
So, um, the way that I do this, and it's a fabulous question
55:28
because back when I was, um, you know,
55:31
back when I was a resident, um, positioning was, it's,
55:34
it always is really, really important.
55:36
And I was fortunate where I trained that there was a lot
55:39
of focus, uh, with our technologists
55:42
to make sure the patients were straight in position.
55:45
Oftentimes, what happens,
55:46
it can be really confusing if the patient's not perfectly
55:49
aligned in the scanner,
55:51
but what you can do is that you can acquire the,
55:53
if you're using a multi detector imaging
55:55
and you're acquiring it as a volume metric acquisition,
55:59
you can just go in and take the line
56:01
and just do a MPR reconstruction, the axial plane,
56:05
and then you can align that patient perfectly.
56:08
And it's a very practical question.
56:09
I do that every day in my practice
56:11
because sometimes the text just, you know, they're,
56:13
they do a great job, but sometimes you'll have
56:16
that occasional patient where it's kind of hard to do it.
56:19
So I take that volume data and I do my NPRs
56:22
and I just kind of tilted in the, um, in the axial plane,
56:25
so I know it's symmetric.
56:31
How do you visual, how do you see for vocal cord palsy?
56:36
Yeah, so as I mentioned
56:37
before, the vocal cord palsy, what I look is
56:39
for asymmetrical thickening of the
56:42
right area epiglottic fold, and if there's thickening
56:46
and ipsilateral dilatation of the piriform sinus,
56:51
then I start thinking about vocal cord palsy.
56:54
So you have to have a paramedian cord, you have to have,
56:57
oftentimes it's thick,
56:59
and then the right piriform sinus is ipsilateral dilated.
57:03
So those are the three things that I look for.
57:07
And even when I do see this,
57:09
I still will recommend an endoscopy
57:11
to make sure there's not an underlying neoplasm.
57:17
How do you identify paralytic spread at glottic level?
57:21
Uh, that is a really, really great, great question.
57:23
So, um, one thing that I will say is that,
57:28
um, you know, let me go to this slide.
57:31
Let me go to the slide. I remember, let's see.
57:36
Yeah, here's a, here's probably a good example.
57:38
Can you see my slide, Ashley?
57:42
Yes. Okay.
57:43
So the challenge that, that, that I've run into is
57:46
that back when I was a fellow, and I always say that,
57:49
but I can say it now 'cause I'm old.
57:51
I, I was, I was born in the last century, if you will.
57:54
When we, when we did our imaging, you know, 25 years ago,
57:59
the slice sickness that we used to get was somewhere between
58:03
anywhere from two millimeters to three millimeters.
58:06
And when you did the two to three millimeter slices,
58:08
oftentimes we would sometimes pick off like maybe the base
58:13
of the false vocal cord and the true vocal cord.
58:15
And oftentimes you could see the paranal fat right here.
58:19
The challenge is, is that now we're doing very,
58:21
very thin sections
58:23
and the, the retinoid muscle is pretty thick.
58:27
It's really hard to actually see the paralytic space
58:31
at the level of the true vocal cords.
58:33
I think it's just really, really hard to see.
58:35
So I think what we first described 30 years ago,
58:38
oftentimes we were probably doing a
58:40
little bit of partial volume.
58:42
So I have a hard time seeing the paralytic space right
58:45
at the true vocal cords.
58:47
Now, at this level, I'm at the false focal cord,
58:49
and at the false vocal cord,
58:51
then I can see my tiger stripes.
58:53
I love talking about tiger stripes.
58:55
So I can see the cartilage here, I can see the black fat,
58:58
I can see the lateral thri muscle, and I can see the fat.
59:03
So once I get above the true vcal cords, um,
59:07
the medial thyroid mo mo muscle tends to peter out,
59:11
and you can have the little strip of the lateral oid muscle.
59:14
So I think it's easy to see the level of the false quats
59:17
as opposed to the true chords.
59:22
All right. If a tumor extends anteriorly
59:25
through a non ossified midline defect of the thyroid
59:28
car cartilage without cartilage invasion,
59:31
would this still be T four?
59:34
Uh, so lemme see now.
59:36
Um, which que Yeah, that's a good question.
59:39
So which one was that one?
59:40
That was on the Q and a right? I wanna make sure
59:43
Q and a. Yeah, the one all the way
59:44
at the top.
59:45
All the way at the top. Okay. Yes. Okay.
59:50
So the question is, is it's a great question.
59:53
If a tumor extends anteriorly through a non ossified,
59:57
oops, I just lost it.
59:58
A non ossified cartilage, thyroid cartilage,
60:02
is it still a T four?
60:03
So the answer is yes. So the cartilage doesn't have
60:07
to be ossified, the cartilage
60:09
before it becomes ossified is cartilaginous.
60:11
So if the tumor extends through the inner
60:14
and the outer cortex, even if it's non ossified,
60:17
it is still a T four, it is still a T four.
60:25
What do you prefer for cartilage invasion, MRI
60:28
or dual energy ct?
60:31
Um, I like, um, uh, well, you know, there have,
60:34
there were a couple of papers written a while ago on,
60:36
on dual energy ct.
60:37
In fact, I use that in one of my talks.
60:40
But the dual energy CT is, uh, I don't know how, uh,
60:45
how reliable it's been shown long term.
60:48
So I would rather do, my preference is to do a regular ct,
60:53
uh, with high resolution bone algorithms
60:56
to look for the cartilage invasion.
60:57
And then I would go to MR as a problem solving technique.
61:00
I don't think, um, I don't think the dual energy CT
61:05
is reliable enough to make a clinical decision as to whether
61:09
or not someone's gonna be, keep their larynx.
61:13
Gotcha. This might be related, uh,
61:16
why use dual phase IV contrast injection technique?
61:19
Yeah, so the reason is, is to make sure
61:22
that you have enough time for the contrast
61:24
to infiltrate the tumor and the soft tissues.
61:27
Because if you, if you inject
61:32
and then acquire, you're gonna be doing CTAs on everyone.
61:37
So when you do a CT, the neck, what you want to do is
61:40
optimize the contrast going into the tumor
61:43
and the soft tissues.
61:44
And you also want to make sure
61:46
that when you're looking at your neck, cts,
61:48
and this is a good example, here, you have a ification
61:51
of your arteries and you have a ification of your vein.
61:55
So the dual phase allows you to do both of those.
62:00
What role does, did the diffusion sequence play?
62:05
Um, I think diffusion sequence in the larynx can be a
62:08
little challenging because there's so much motion.
62:11
What the way that I use diffusion, um, is
62:14
that if I see a mass in the head
62:16
and neck, I re, I always rely on the location
62:22
and the normal appearance on the standard sequences
62:26
to help me determine whether it's benign or malignant.
62:29
But if there's something I'm not sure about,
62:31
then I turn to the diffusion.
62:34
Now some people have used diffusion to differentiate
62:37
between post-treatment changes and recurrence.
62:40
Um, I think that's good, so long as your technique is good,
62:45
so long as there's no motion,
62:47
and then the mass that you're looking at is, you know,
62:51
probably greater than a centimeter
62:52
because the smaller the mass, the harder it is
62:55
to reliably see on diffusion sequences.
63:01
Thank you. What is the big five again?
63:05
So the big five are the epiglottis,
63:11
the thyroid cartilage, the retinoid cartilages,
63:17
the false fo uh, excuse me.
63:19
Actually, hold on for a second. Lemme just go back to my,
63:21
let me go back so I don't mess it up.
63:23
So here's the big five right here. You ready?
63:26
So the big five for the larynx are going
63:29
to be the hyoid bone, the epiglottis, the thyroid cartilage,
63:35
the retinoid cartilage, and the cricoid cartilages.
63:38
Those are the big five of the larynx.
63:42
Thank you. What comprises the posterior
63:45
commissure of the larynx?
63:47
Yeah, great question. So terrific questions by the way.
63:51
Um, yeah, keep them coming.
63:53
So the, the posterior commissure
63:56
is the posterior portion of the larynx that's located
64:00
between both the retinoid cartilages.
64:03
So when I show, when I show this image right
64:07
here, can you see this?
64:10
Uh, can you see this Ashley? Yep.
64:14
You guys see how great Ashley is? She's amazing.
64:16
So here is the crico cartilage smiling at us, right?
64:19
Ashley, you can see it's smiling, right?
64:21
I'm gonna turn you into a head and neck radiologist. Okay.
64:23
So there's the crico cartilage.
64:25
Here's the retinoid cartilage,
64:26
here's the crico retinoid joint.
64:28
So the posterior commissure is located
64:30
between both crico retinoid joints.
64:33
That's the posterior commissure.
64:34
So it's just mucosa overlying the, uh,
64:39
inner cortex of the crico cartilage.
64:41
And this area anterior is gonna be the anterior commissure.
64:49
Right. All right.
64:51
How do you determine the level
64:52
of tracheal rings if the tumor extends
64:54
below which place is best to see which rings are involved?
64:59
Yeah, that's a great question.
65:01
So, um, again, something that, uh, that we try
65:04
to do every day, albeit it's kind of rare
65:06
because most tumors
65:07
that extend into the sub glottic larynx don't extend all the
65:11
way through the base of the cryo cartilage.
65:13
So what I end up doing is the,
65:16
and I don't have an example of this,
65:18
but there's, there would be an axial image
65:21
that will basically look at the, the last remaining ring
65:26
or the cartilage, the cartilaginous landmark.
65:31
So let me see if I can show you this. Yeah.
65:34
So basically this is what the sub glottis looks like,
65:37
and this is the cartilaginous ring.
65:40
Once I get to the base of this cartilaginous ring,
65:43
there's gonna be images where there's no cartilage at all.
65:48
And then as I continue to go the, uh,
65:52
especially in older patients,
65:53
this tracheal cartilage becomes ossified again.
65:57
So in general, the tracheal rings are about
65:59
10 millimeters in height.
66:01
So what I do is once I go through the base of
66:03
that last crico cartilage,
66:05
each ring is about 10 millimeters in height.
66:08
So that's when I begin to count.
66:10
So I just go, uh, no cartilage, cartilage,
66:12
no cartilage, cartilage.
66:14
And then I can just, now I,
66:15
with multiplanar reconstructions, I can just, um,
66:19
use my reference lines to figure out, you know, where I am.
66:22
Regarding the, the, the tracheal cartilages
66:25
or the tracheal rings I should say.
66:31
What is the role of pet CT in small laryngeal tumors?
66:36
Uh, that's a great question. Um, it's a fabulous question.
66:41
Um, you know, it really depends on who you ask.
66:45
I think in general, um,
66:47
early laryngeal carcinomas probably do not need
66:50
to undergo a pet ct.
66:53
So from my own standpoint, I don't think you really need
66:56
to perform pet CT to evaluate the primary site
66:59
for early laryngeal cancers.
67:02
But a lot of my referring physicians end up doing PET cts
67:06
to look for distant metastases.
67:08
So I think that really varies with the practice.
67:10
If you ask me, do you need to do a pet CT for
67:14
early laryngeal carcinoma, my answer is, is no.
67:20
Great. Do you ever image using
67:25
constant donation to keep the vocal cords separated?
67:29
No, I don't. Simple answer.
67:37
All right. Trying to find, oh,
67:40
is there any demarcation line between the end of glottis
67:43
and beginning of sub glottis,
67:44
or do we consider all sections below the level of preco
67:48
adenoid joint as sub glottis?
67:51
Yeah, that's a great question.
67:52
Um, there's no real, it's a fabulous question.
67:55
Keep 'em coming. Um, no, you really don't.
67:58
I think, um, like, uh, there was one case
68:02
that I showed like this, this image right here.
68:04
So here's the CRICO cartilage, here's the OID cartilage.
68:07
Basically this CRICO cartilage is, if you will,
68:10
still sort of smiling at us.
68:11
So this is really just a few millimeters below this.
68:15
This would be about as close as I could get.
68:18
But essentially when I look at the CRICO retinoid joint
68:22
and then I start looking below
68:24
and I completely lose the retinoid cartilage,
68:27
then I know I'm in the sub glottis.
68:29
And this really correlates with the anatomy, right?
68:32
So if I see the CRICO OID joint here,
68:36
if you look at the cricoid cartilage,
68:37
this back portion's a little bit
68:39
higher than the front portion.
68:41
So once I get below the retinoid,
68:43
I may not see the complete circle,
68:45
but I know that once I, uh, the OID becomes absent,
68:51
then I know I'm at the level of the sub glottis.
68:53
So that's kind of what I use to make
68:55
that very subtle separation.
68:59
Right. And since we're, we are on vocal cords here,
69:02
we got a couple questions regarding that.
69:04
Can you comment on vocal cord fixation on imaging?
69:08
Um, yeah. Um, so number one,
69:13
vocal cord fixation,
69:14
really the definitive way, sorry about that.
69:16
The definitive way to look at this is at endoscopy.
69:21
So when you look down
69:22
and you perform endoscopy,
69:23
the surgeons always ask the patients
69:25
to do vocal cord donation.
69:27
And specifically this happened, yes,
69:29
in clinic they have 'em do make a high pitch.
69:32
And when you do that, it kind of closes the vocal cord.
69:35
So that's results in the opposition of the courts
69:39
for vocal cord fixation.
69:40
What ends up happening is
69:41
that the true vocal cord becomes fixed to the midline.
69:44
So I think I may have had one example, um, let's see,
69:48
I think it was under trans spread.
69:52
Yeah, this vocal cord, right,
69:53
this vocal cord right here is a little bit more midline.
69:57
Um, and so basically that cord just gets pushed to midline.
70:01
The reason why I'm really comfortable saying
70:02
that this was midline is that when I looked at the false
70:05
vocal cord and I see this tumor involved in the false cord,
70:09
then I know that there's enough mass
70:11
effect to push it midline.
70:13
So in general, you know, something like this,
70:16
this doesn't necessarily be the
70:19
midline, it's just thickened.
70:20
But what I would suggest you do is not comment on
70:24
vocal cord fixation on CT scans.
70:27
Vocal cord fixation is a dynamic movement
70:31
and that dynamic movement is easily seen at endoscopy.
70:36
So don't spend your time talking about if you will fixation.
70:39
But what you can do is comment on the tumor, the thickness
70:43
of the cord, whether it's subglottic
70:45
or whether it's trans glottic,
70:48
those things cannot be seen oftentimes at endoscopy
70:51
or clinical examination.
70:53
But the fixation, you can suggest vocal cord fixation,
70:57
but I really wouldn't put that, uh, in your, in your report
71:00
unless you wanna say something that says
71:03
these findings are suggestive of, uh,
71:06
a paralyzed or a fixed cord.
71:08
But in general, that's secondary.
71:11
What you should be commenting on is the, the thickness,
71:13
whether there's a tumor
71:14
and the superior, the inferior spread,
71:16
and whether there's cartilage erosion.
71:18
Those are the main things that I would focus on.
71:24
I'm glad you're on this slide. Uh, regarding images on CT
71:27
of vocal cords, they tend to be blurry.
71:30
Any advice on how to get them a little crisper?
71:34
Are you talking about my
71:35
pictures or the other ones? I think
71:37
J just in general, there's a question about general images
71:40
on CT being a little blurry.
71:42
Yeah, yeah. I think, um,
71:44
I mean these are pretty crisp for me.
71:45
Maybe, uh, they be crispr
71:46
but um, in general, um, um, there,
71:50
there's a fine line that we run into.
71:53
And so the more higher the dose that you give, you know,
71:57
the more crisper your images are gonna be.
71:59
But you have to be cautious
72:02
because I remember, I still remember the, I, I remember
72:07
where I was the day when the,
72:09
the ring like alopecia was first
72:12
reported in patients undergoing CT perfusion
72:15
and all of a sudden everyone dropped
72:17
their dose the next day.
72:18
So there's a fine line between
72:20
giving an optimal amount of radiation dose.
72:23
So you can see the image in the perk anatomy,
72:25
you can always give more dose,
72:27
but on the other hand, you don't wanna overdose patients.
72:29
So you wanna make sure that your dose is, uh, optimized.
72:34
Number two, you wanna make sure that the patients,
72:37
um, hold still.
72:39
And number three, especially if you're using, you know,
72:42
a modern scanner, the scanners have different types
72:45
of algorithms right now, you know,
72:47
they have different algorithms for soft tissue algorithms
72:50
and bone algorithms.
72:52
And if you look at your parameters
72:53
and you say, well, my MA is good, my KVP is good,
72:57
the patient's held still
72:59
and I'm doing my slice sickness sub-millimeter, well
73:03
that tells me you may want to go to your scanner to see
73:06
how your technologists are actually
73:08
reconstructing in soft tissues.
73:09
'cause it could be a fixable problem just by changing your,
73:13
the algorithms, your soft tissue algorithms on your scanner.
73:21
Alright, um,
73:26
can you, can you talk about the pre epiglottic space?
73:30
Yep. Great question. I have a great slide for that one.
73:35
So the pre epiglottic space
73:38
is right here.
73:41
Can you see my screen, Ashley?
73:43
Yes. Yeah.
73:44
So this is the epiglottis that's located here
73:47
and the fat that's anterior to the epiglottis.
73:49
This is the pre epiglottic fat, also known
73:52
as the pre epiglottic space.
73:55
So there was a image that I showed of a patient,
74:00
I think it was under the Trans Glo one.
74:03
Yeah, it was right here. Yeah.
74:05
So here's an epiglottic carcinoma, it's anterior midline,
74:08
it's also involving the right every epiglottic fo but,
74:11
but most of it's anterior midline.
74:13
And you can see how you can see the fat here on the left
74:16
hand side, see how the fat on the right is gone.
74:18
So basically when you look axially, it's this fat
74:21
that's anterior to the epiglottis.
74:23
And if you see that, that upstages these
74:25
lesions to a T three.
74:27
So this is, uh, the pre epiglottic space
74:30
or the pre epiglottic fat.
74:35
Alright? Uh, sometimes post-radiation changes bluff
74:39
for residual tumor.
74:41
What do you do then?
74:43
Yeah, bluff. Um, so that's sort of a talk into itself.
74:47
You know, in the future we could have a talk on, you know,
74:49
post-treatment imaging.
74:51
But, um, the long and the short of it is, uh, let me see.
74:57
So this is an example.
74:58
This was a patient that was pre-treatment
75:01
and this is post-treatment.
75:02
And the, the point why I wanted to bring this up is that
75:06
this can, if you will, sometimes bluff for recurrent tumor
75:09
because it kind of looks big and nasty.
75:12
But what I look for is I look for, um,
75:15
symmetric thickening after radiation therapy.
75:19
So notice how the submandibular glands have become atrophic,
75:22
all of this epiglottis,
75:24
this is the median gloss of epiglottic fold.
75:25
This is one molecular, this is the other molecular.
75:28
Notice how the changes are all symmetric.
75:31
Here's another example.
75:33
This area right here,
75:34
these area epiglottic folds are, this is normal.
75:38
You can see this after radiation and chemotherapy.
75:41
In this case, and this is a different talk,
75:43
but this was an example of laryngeal or con necrosis.
75:46
'cause there's air into the soft tissues.
75:48
But the point that I wanna make is that what I look
75:51
for is I look for symmetric thickening and low attenuation
75:55
after radiation therapy.
75:56
So I look for that symmetry.
75:58
If I see something that
76:01
after treatment ends up having a, uh, uh, uh,
76:04
an asymmetrical soft tissue mass, you know,
76:07
like here's an example of a recurrence here,
76:10
then I start thinking about recurrent disease.
76:13
But in general, the changes
76:14
after radiation therapy, you know, are symmetric.
76:20
Thank you so much for that.
76:22
We're gonna do two more questions and then and wrap.
76:25
Can you give a brief rundown
76:26
of the different ENT laryngectomy types so we know,
76:31
Um, yeah, yeah, sure.
76:33
So there's um, there's actually a whole bunch.
76:37
Um, but let me try to, um, let me try to,
76:41
uh, consolidate for you.
76:42
Okay. So this is an example of
76:46
a patient in which the epiglottis,
76:49
the area epiglottic foss in the false course were resected.
76:53
So after surgery, all we see here is the true vocal cord.
76:57
This is what's referred to as a Supra glo laryngectomy.
77:02
A total laryngectomy is obviously when the whole
77:05
larynx is resected.
77:07
Now this is the standard type of procedure if the tumor
77:11
stops above the level of the true V cord.
77:14
So when we talk about supraglottic laryngectomy,
77:17
it's predominantly done for supraglottic cancers.
77:21
Now this is an example of a standard hemi laryngectomy.
77:26
So in this case, what we see is that this, this type
77:30
of surgery is predominantly performed for a patient
77:34
that has a true VCO cord carcinoma.
77:37
So what happens here is that in this particular case,
77:40
there's a true VCO cord carcinoma.
77:42
There is no trans glottic spread.
77:44
So the surgeon can make their cut, they can take, remove one
77:49
focal cord, and they remove a part of the thyroid cartilage
77:53
and that way the patient can preserve part of their voice.
77:57
So this is what's referred to as a hemi laryngectomy.
78:00
And there's also types, as I kind of alluded to earlier,
78:04
where you can have micro dissections
78:06
or micro laryngectomies if you have early stage tumors
78:09
involving the larynx, well they can resect
78:12
that using some type of laser.
78:13
So in a way those are kind of, you know, three
78:17
or four different types of laryngectomies.
78:19
I, I have a full lecture on different types of, of,
78:22
of laryngectomies, um, as,
78:25
but that would take another 30 minutes.
78:29
We'll have to schedule, schedule that
78:31
for our next noon conference.
78:34
Alright, last question.
78:36
What about per, how do you handle
78:41
a peritumoral tumoral edema on, on CT
78:44
that might look more like an advanced tumor?
78:47
That's a great question.
78:49
Um, so the, the bottom line is we really can't tell,
78:53
you know, um, if, if, if, if, if I see a tumor
78:57
and I wanna see if I have an example of this, um,
79:00
if I have a tumor, um, for instance,
79:04
if I see this tumor here extending
79:06
to the anterior commissure and I look lateral
79:08
and I see a little bit of thickening right here, you know,
79:10
is that a tumor or is that edema?
79:12
You know, I don't know for sure.
79:14
What's more common is that, um,
79:18
the tumors involving the head and neck.
79:20
Um, and it's especially prevalent once we talk about
79:24
tumors involved in the tongue base and the tonsil
79:27
and the, the, and the oral tongue cancers,
79:30
they have a very robust peritumoral inflammation.
79:33
So it's not edema, but it's peritumoral inflammation.
79:37
And sometimes the pathologist,
79:39
and especially when we're looking early years ago
79:43
when we were actually looking at our ability
79:45
to detect cartilage invasion, some of the cartilages
79:49
that were taken out had no evidence of tumor at all
79:52
and it was just peritumoral inflammation.
79:55
So principle number one is that yes, head
79:57
and neck cancers are real.
79:58
Number two, these head
80:00
and neck cancers elicit a very robust peritumoral
80:03
inflammatory response.
80:06
Number three, it's almost impossible for us to distinguish
80:11
between a very robust peri tumor response
80:14
from the tumor itself.
80:16
So that's why when you look at these sensitives
80:19
and specificities, there's not a hundred percent.
80:22
So when I, uh, and going over, especially with MR imaging
80:26
because we're looking for replacement of the marrow fat,
80:30
not necessarily the erosion of the cortex,
80:32
but the replacement of the fat.
80:34
And this is not only for cartilages,
80:36
but for bone erosions, for oral tongue cancers
80:39
or for oral cavity cancers, I always say
80:43
the marrow is replaced.
80:46
I don't know whether it's definitely due to tumor
80:48
or whether it's due to inflammation.
80:50
If I know that the bone is eroded for sure,
80:53
then I have a higher likelihood of saying
80:55
that replacement is due to tumor.
80:57
But if the cortex is intact and I do an MR
81:00
and then I see replacement by this peritumoral inflammation,
81:05
I just say that to our clinicians
81:06
and I'll say, this is what it is.
81:09
You have to decide internally whether
81:10
or not you wanna do a mandi ectomy
81:13
or do you want to assume it's just due to inflammation
81:16
and treat it with, you know,
81:17
radiation chemo after the treatment.
81:19
So we can't tell a hundred percent,
81:23
but what I do try to do is when I review this
81:25
with my referrings, I always give them the scenarios
81:29
and let them make the decision based on the best, uh,
81:32
educated, uh, information.
81:35
Wow. Well thank you so much Dr.
81:37
McCury for the amazing lecture
81:39
and for answering all of those questions.
81:42
There's still so many to get to.
81:43
Um, I wish we had all the time in the
81:45
world. Thank you so much.
81:47
Great. And thanks Ashley for everything.
81:49
Thanks for all of y'all. We said still have over 250 people
81:52
on the line, so appreciate you guys taking the time and,
81:55
and, um, medal.
81:56
Thanks for everything you guys do. Absolutely.
82:00
Happy to come back in the future too.
82:02
Yes, definitely. Yes.
82:03
And thank you everyone for participating
82:05
with the amazing questions and and chats.
82:07
It's um, this is why we do these new conferences
82:11
and you will be able to access the recording
82:12
of today's conference
82:14
and all our previous new conferences
82:15
by creating a free MRI line account.
82:17
We will also be sending the replay of this out via email,
82:21
with email that you registered for the Zoom.
82:23
So look for that.
82:25
Be sure to join us next week on Thursday,
82:28
February 15th at 9:00 AM Eastern, where Dr.
82:32
Alka Singhal will Deli deliver a lectured entitled current
82:35
uses of ultrasound ela.
82:37
Thy you can register for this free lecture@mrionline.com
82:41
and follow us on social media
82:43
for updates on future noom conferences.
82:45
Thanks again and have a great day. Bye.
Suresh K Mukherji, MD, FACR, MBA
Clinical Professor, University of Illinois & Rutgers University. Faculty, Michigan State University. Director Head & Neck Radiology, ProScan Imaging
© 2026 Medality. All Rights Reserved.
