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I'd like to talk for just a moment about the duct of the

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parotid gland which is termed the Stensen's duct.

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This duct runs from the parotid gland superficial

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to the masseter muscle, and then as we said,

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it will pierce the buccinator muscle and enter the cheek

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opposite the maxillary second molar region.

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This is something you can actually look at in the mirror

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tonight and identify your parotid duct orifice at the...

0:33

in the cheek opposite the second maxillary molar tooth.

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I've done some

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sialography in the past and this is a duct that has

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a very tight kind of orifice and is difficult to cannulate.

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And you do so with very, very small catheters,

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and you can inject contrast dye into the parotid duct,

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into Stensen's duct with an injection of

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about 1 CC of contrast to opacify it.

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There may be an accessory lobe of the parotid gland

1:11

overlying the masseter muscle, which has an accessory

1:14

duct which will communicate with Stensen's duct.

1:19

I'm going to take the opportunity to show you this case

1:24

which has multiple parotid calcifications

1:28

in order to identify the duct for you.

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On these slides,

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you see multiple calcifications

1:38

in the parotid glands bilaterally.

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Now,

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I tend to use the term parotid calcifications rather

1:50

than calculi in the parotid gland when it's a diffuse

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process which could be on the basis of metabolism

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and disease entities that can cause

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calcium phosphorus dysmetabolism.

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However,

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most of these are found in tiny little ducts

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or in the acini of the parotid tissue.

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In this case,

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the reason why I'm showing it is because of this

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particular stone here.

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Now this is in the duct.

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So this is a ductal stone.

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So we use a term that has lots of syllables.

2:27

Sialolithiasis is calcifications within the salivary glands,

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and you might say sialodocholithiasis,

2:43

docho referring to the duct.

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So a calcification, a stone that

2:49

is within the duct itself.

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So, in this case,

2:53

what we see is the opening of the

2:57

Stensen's duct into the buccinator muscle

3:00

opposite the second maxillary molar tooth.

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And we have a proximal stone

3:08

or sialolith

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and it's causing some element of dilatation

3:16

of the duct superficially.

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On the contralateral side,

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we're sort of missing the duct entry.

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It's probably right here, faintly seen,

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not dilated the way the right side,

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which is abnormal is.

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Remember, as I said on a previous demonstration,

3:43

that there is a little slip of a muscle that comes

3:47

more superficially and actually inserts

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anteriorly, the zygomaticus muscle.

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This is one of the muscles of facial expression.

3:57

I want to show one more case.

4:00

This was a patient who was traumatized,

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was punched in the face and had development of a soft

4:07

tissue mass on the side in which he was punched.

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And I was asked to do a sialogram to identify where the

4:18

mass was in relation to the salivary gland.

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As you can see, this is somewhat of an old study.

4:25

This dates back before we had MR sialography,

4:30

which is really quite good for demonstrating

4:32

the ductal system.

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However, the value of this case

4:36

was the fact that I was able

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to demonstrate that this mass was a sialocele.

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So here is the duct,

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and I was able to cannulate the duct

4:50

in the buccal tissue, adjacent to the second maxillary

4:54

molar tooth, and then inject contrast dye.

4:58

And you see that contrast dye here filling the duct

5:03

as well as some of its tributaries.

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After filling the duct,

5:07

we did a CT scan,

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and what it demonstrates is this large

5:13

iodinated contrast

5:17

containing cyst that is communicating with the duct.

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In an area where the patient had been traumatized,

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you can see some of the subcutaneous ede...

5:31

subcutaneous edema here from the punch in the face.

5:37

So the mass that the patient had developed actually was

5:40

in communication with the ductal system,

5:44

and that entity is known as a sialocele,

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and it was filled with a contrast dye

5:53

and identifying it as such

5:55

as opposed to a tumor mass, that was the main concern.

5:59

So this is another demonstra...

6:01

just a demonstration of opacification

6:04

of the ductal system with iodinated contrast

6:07

in a patient who had previous trauma.