Interactive Transcript
0:05
So this was a pace that presents with a mass right here involving the right
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protic gland.
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The thing about this mass is I think some people ended up saying an abscess,
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which is reasonable, but the patient was, um, essentially afebrile.
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So they didn't have any signs and symptoms of inflammatory processes or, or,
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or an infectious process.
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So if you do see a cystic mass like this involving the parotid gland,
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especially in the us so granted,
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if I was in India and I saw something like this and maybe in,
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maybe in Malaysia too,
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then you'd have to think of some type of endemic infections,
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like maybe neuro cystic psychosis. But in general,
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it's kind of rare to have a single isolated cyst like this.
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But the most common congenital lesion that you end up seeing in the
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parot gland in a child is gonna be a first brachial anomaly.
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So I did bring this up.
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So the brachial anomalies is that basically they arise from the brachial
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arches. So you know, there's the first brachial um, arch,
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the second brachial arch, et cetera.
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So the first brachial groove gives rise to the external
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auditory canal. So when you're actually looking at the embryo right here,
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this is the first arch and this is the second arch.
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So this area right here ends up forming the external auditory canal.
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So this is again,
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a schematic illustration of the formation of the external
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auditory canal is here, the middle ear Kathy is here,
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and where this just move this, get it outta my way. Um,
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where the
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couch and the external auditory, uh,
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groove form ends up forming the tympanic membrane.
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So what the first brachial arches is that it is,
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there are two types. There's a type one and there's a type two.
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So the type one,
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they're both felt to be duplications of the first brachial apparatus.
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And a type one is basically an intracarotid cyst.
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And we'll see the type two later.
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This is a small little fistula that forms at the junction of the ex,
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the external laboratory canal at the members and the bony junction.
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And it forms a little fistula right here that extends all the way down and
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typically into the region of the submandibular space. So again,
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these are examples of type one first brachial anomalies.
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You can see basically there's cysts right here.
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So if we go back and then look at this case,
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what we see here is the cyst that's involving the parotid gland in an afebrile
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patient. And that turns out to be a first brachial cleft cyst.
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Um, such this should say a type one first brachial anomaly.
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Now what I did wanna say is that, you know, if you do see pure cyst in adult,
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what I have noticed is that if this ends up,
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let's just say this never presented in the child,
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but it ends up presenting an adult,
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then this could be due to quote unquote a parotid cyst.
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It could be due to a unilateral um, salal. But, um,
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years ago we did this study where we actually correlated, um,
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pathology with first brachial anomalies, excuse me,
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I should say congenital anomalies. And what we found out in adults,
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a certain percentage of these that present with these asymmetric a asymptomatic
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intra paric cysts are actually type one first brachial anomalies.
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So let me stop there and then you can ask any questions you want to on this.
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So in, uh, in it still can be the first anomaly.
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Yes, yes. Type one first anoma. Exactly right.
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So there has to be at least included in the differential diagnosis for purely
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cystic lesions for purely cystic,
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Not only the cystic. Yes. Not only the cystic metastatic lymph node.
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For oral pharyngeal ca
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Uh, it would be unusual to have a inid cystic lymph node
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for oral pharynx.
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So that cystic mass was in an adult in a level two lymph node
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that a hundred percent that then you'd have to consider that. Okay.
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The fact that it's actually within the parotid gland. And that makes, um,
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it very unusual.
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This one initially I thought is a part of the says.
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Mm-hmm. Yeah, yeah. Which is reasonable, which is, I remember I saw your report,
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I think that was very reasonable.
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But I think in the comments when I graded your report, I think I said, well,
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the only thing is that there was no history of it.
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'cause I very rare to see type one brain Q anomaly because 80% will be type
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two.
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No, just the opposite 80% are gonna, well, no, hold on for a second. Now.
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So realize,
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I mean the, for the type two brachial anomaly,
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not the type two first al anomaly,
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Right? I think so just to clear up the, the, the, the, your lexicon,
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there's first brachial anomalies in which
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Or second Yes.
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Type one and type two first, brachial anoma,
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then there's second brachial anomalies.
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And I think what you're saying is that the most common brain anomaly second is a
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second, right? That's correct. That's exactly right. Very good.
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Because for the second itself, there are four types.
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Yes, that's exactly right.
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Con confusing. Yes,
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Exactly right. How did you learn that? Did I, did you, do you remember? I,
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'cause I
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Saw most of,
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I think I saw most of the patient with the second er
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and normally I seen the sinus fistula,
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different types of second er. Yeah. And normally in my practice,
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Yeah. Oh, that's good. Do you see this, do you see the diagram here?
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So this is the four types of second brachial anomalies.
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So you have one,
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the type ones are typically involving the skin and the platysma muscle.
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So this is path proven type one second.
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This was the classic type two second.
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So when you look at the second brachi anomalies,
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the type two is the most common.
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The type three extends between the internal and the external carotid artery,
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and it actually visualizes to the tonsil. So for me,
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the way I remember this is that if they actually do a fistulagram and you see
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the fistula extending all the way to the tonsils,
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and then it's going between the internal and the external carotid artery,
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then that's a type three.
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And the type fours are located deep to the plane of the internal and the
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external carotid artery. So again, it's a little bit more common than,
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than you would expect. So I think a lot of these are sometimes referred to,
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or they may be misclassified as these a para pharyngeal cyst or
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a,
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a consular cyst or a cystic retropharyngeal mass.
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But, uh, just in the back of your mind,
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you have to realize if it's purely cystic and the patient's asymptomatic,
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it actually could be a type four brachial cleft, uh,
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a type four brachial arch anomaly. In fact,
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there was a case about 15 years ago where we saw this and I thought it was gonna
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be like a cystic parotid lymph node, but one of my colleagues say,
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could it be a type four second? And it turned out it was a type four second. So,
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uh, just realized if you have these pure cyst, you know, in,
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in addition to a tonsor cyst, it could be a type four brachial, uh,
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type four second brachial cleft cyst.
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And you might, uh, show us the third and four,
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because it's very hard to differentiate between the two. Yep,
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Sure can. It's actually, you know, it's not that hard. Um,
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and I'll tell you why. Okay. So, so you got the, we'll,
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we'll go over the first, right? So we talked about type one first,
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and I think another case is gonna be at type two first. You got that right?
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Mm-hmm. And then we talked about the second,
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which is predominantly involving the tonsil, right? So you got this here.
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Mm-hmm. The type three are actually more common than you think they are.
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So the type three is associated with the piriform sinus,
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and then it crosses between, um, it,
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it actually crosses posterior to the internal, uh,
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carotid artery and runs between the ninth and the 12th nerve.
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But the key thing here is that it's located in the posterior triangle.
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So the,
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the one here on the left was actually pathologically proven third brachial
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anomaly. It was a third brachial cyst and they,
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they took it out 'cause I thought it was gonna be a metastatic lymph node,
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but this was actually a pathologically proven third brachial anomaly.
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And then the more common appearance is that if you have this little cystic mass
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that's located in the posterior triangle,
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this was actually a pathologically proven third brachial anomaly.
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So the way to think the thirds is that if you see a cyst right here,
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that's tic lesion, that's actually posterior to the,
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the external carotid artery. You know, the number one that you,
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that you think about is gonna be a lymphatic malformation,
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but it is the second most common lesion to involve the posterior triangle.
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So that's the way the third is.
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And the other thing for the third, uh, oh yeah, that's, that's the third.
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So the next one is gonna be the fourth. Now I have to admit, I've seen,
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I have seen a lot of confusion as to what's the, what's a third and a fourth.
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The way that I look at it is that I know that the fourth starts
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at here, at the piriform of sinus, goes up and then comes down, okay,
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that's the embryology of the third.
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The fourth is actually pulled down.
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It's actually tethered down down.
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So the fourth can also pierce a thyroid hyoid membrane.
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And there's some controversy as to the difference be where the fistula is gonna
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be, be between the third and the fourth.
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But in general the fourth is right at the apex. So if it's at the apex,
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they tend to extend more inferiorly.
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So this was a patient of a fourth brachial anomaly because it was involved in
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the apex. And notice,
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here's the piriform sitis here and see this little lesion extending down
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inferiorly.
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And these are the ones that typically present with recurrent thyroiditis or
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recurrent anterior neck masses. And then they can,
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they can continue to extend all the way down into the mediastinum.
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So one more example here. This is the, uh, type one first.
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So this is actually in the Prada gland.
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This is a type two first because we can see this area extending here into the
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extra laboratory canal. These are the four types of second.
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So that's involving the skin. This is the classic type two second,
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this is the type three third, and then this is the type four, uh, excuse me,
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type three second. And this is the type four second path proven here.
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And then this is an example of a third bronchial anomaly.
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Notice how it's involving the posterior triangle and then here's an example of a
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fourth brachial anomaly.
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And notice how it's involving the piriform sinus and presenting with recurrent
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anterior neck masses. So those, the way that I classify them, and I think it's,
11:01
I think that's what most people do. Does that answer your question?
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Yeah, it's very clear explanation. Okay, good. Excellent.
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I think a few days ago I saw a patient with the, looked like a four,
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four ular anomaly with the abscess in near the visitor space.
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It's very unusual. Mm-hmm. Without any foreign body injection.
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Maybe that kind of patient may, may have the foot Brinker anomaly. Right.
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Was it a child or an adult?
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Oh, it's an adult.
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Adult, okay.
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Any uhhuh?
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Yeah, no. Be, um, you know,
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one thing you can do if you're wor if you're concerned about is make sure you do
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the reconstructions. Because sometimes you may not be able to see on the axials,
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but if you did have anterior neck infections, make sure you look at the,
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the coronals. I had a case of that too actually recently,
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and I was sort of raised the possibility of a fourth as well.
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So what,
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so I look in the Corona to look at any communication with the apex or the
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sinus?
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Yeah. Just in case. Sometimes if you look real closely,
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you'll see a little air pocket. If you see something like that,
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that make sure you do your reconstructions.