 All right, moving on, salivary cysts. We'll talk about a variety of salivary cysts like ranulas, lymphobothelial cysts, the brachial cleft cyst, and simple parotid cysts, and then some things that look a lot like cysts, like lymphadenitis, the Wharton's tumor, which we discussed in ductal dilatation. So here's the classic appearance of a diving ranula. This looks like any cystic neck mass until you see the tail that extends into the floor of mouth along the expected course of the sublingual gland. That's our clue that this actually arose as a replacement of an obstructed sublingual gland, and then emerged down as a pseudocyst into the submandibular triangle. That's our clue that this is a plunging ranula. When you see multiple cysts on both sides, think about lymphobothelial cysts that arise in the setting of HIV. These can occur so early they may even precede the seroconversion to HIV positivity in that first six month window. This is a brachial cleft cyst, a first brachial cleft cyst. It characteristically runs parallel to the external auditory canal, and then dives at some point into the external auditory canal, because we can think of these as duplications of that external auditory canal. And sometimes you just get a simple cyst of the parotid. It is a simple cyst surrounded by parotid tissue and nothing more exciting than that. So here is an example where I saw this mass and I saw it was cystic in the center with a lot of inflammation around the outside, and I thought, oh look, it's paralleling the external auditory canal. Surely this is a first brachial cleft cyst. But what I didn't notice was the little bit of surrounding skin thickening that might have been a clue and maybe the thickness of the all would have been a clue that what we're actually dealing with here is a lymph node infected with atypical mycobacterium, which characteristically has a cystic center and some overlying skin thickening. So a mimic here of that first brachial cleft cyst. This is an example of ductal dilapidation in a patient who has chogrens. One might think that this is a mass, but in fact it's just an elongated enlarged duct. All right, let's turn our attention now to infection and inflammation. Infection of the salivary glands can be viral or bacterial, mumps being the famous viral source, and repeated bacterial infections being much more common. Calculator often the source for repeated bacterial infections. Autoimmune disease will also cause inflammation and we'll talk about chogrens disease, myculis disease, and the overarching SICA syndrome, which is the clinical presentation. Radiation changes often affect the salivary glands more than they do the surrounding tissues and can leave you after therapeutic radiation with dense glands that enhance a lot and you just need to be prepared for that in patients who have received radiation. Kuttner tumor is an IgG4 related disease that is a chronic inflammatory disease, but it looks just like a tumor, but it's not its inflammatory disease. And Kusmal's disease is a chronic obstruction of the ducts which is a rare, rare presentation. So here's a classic example of a large stone obstructing stent since duct, causing an abscess to form within the duct itself and extend back into the dilated ducts, a classic appearance for a bacterial infection from psilothiasis. So psilothiasis affects interestingly the submandibular gland more than the parotid gland and the sublingual gland rarely. It's unusual for the submandibular gland to be best at anything compared to its counterparts, but here it is the most commonly affected. 25% of the time there are multiple stones. This is the most common cause of a chronic psilodonitis. Usually there is intermittent obstruction usually associated with eating and stones tend to lodge at particular bottlenecks so you must look for them in particular cases. Unenhanced CT is probably the best way to detect these, although conventional psilography is also good because they will appear as filling defects. Here are the bottlenecks where we should be particularly looking for stones. One bottleneck is at the hylum of the gland where we transition between the intraglangular and extraglangular ducts. That's a bottleneck point, that's where they lodge. The other one is at the puncta just before it drains into the mouth. So whichever gland you're looking at, those are our two bottlenecks. That's where to really look hard for stones. Sometimes the stones are scattered throughout the gland as in this case. These are often an incidental finding in patients who are asymptomatic. Sometimes patients have extremely large stones where you wonder how they could have formed there and spent so long. In fact, these stones you can see are fractured but the fact that these are lined up along the expected course of Orthon's duct is going to be what clues us in to the specific diagnosis of psilolithiasis. Now, Sjogren's syndrome is an autoimmune disease, the most common autoimmune disease to affect the salivary glands. But in fact, it's not just psilatinitis, it's a variety of connective tissue diseases that affect a variety of other organs listed here. Myculeus disease, also called primary Sjogren's, is specific to the salivary glands. There are childhood and adult forms and on psilography, as we talked about, you get a mulberry or a string of pearls sign. Very importantly, these patients have a high risk of lymphoma. In fact, 14 times higher risks than lymphoma. So if you see a mass in the glands of a patient with Sjogren's syndrome, you have to suggest that it might be lymphoma, particularly if it's newer and larger. And Sjogren's syndrome is potentially part of mixed connective tissue disease and that's where a lot of our conventional psilograms come from. Here's another example of that. String of pearls sign where areas of dilatation are interspersed with areas of strictures throughout the interglangular and extra-glangular segments of the duct, a classic appearance for chronic, any type of chronic psilognitis, in this case, the result of Sjogren's disease. And here is a classic appearance on MRI. I think when you see, this is an ant mini, you can set this in your memory. I think if you see the infinite number of slightly dilated ducts with expansion of the parotid glands like this, diffuse enlargement, it is absolutely characteristic. I think you can strongly suggest the diagnosis of Sjogren's disease when you see this picture. So take home points. We must biopsy salivary masses, even if you use your diffusion, your perfusion, your kurtosis analysis, all of these advanced techniques, it's never enough. You need a tissue diagnosis to be confident about salivary masses. When you're looking for stones, look at the bottlenecks at the hyalum and at the puncta. Look for perinural spread from malignancies and don't forget the auricular temporal nerve that comes into the infotemporal fossa. And remember that ectopic salivary tissue is a normal variant and you can see accessory lobes across the floor of mouth. Thank you so much for this opportunity.