 Dr. Mather welcome. Thank you so much for being here. It's a few questions. It looks like we've got a few already in the Q&A box if you want to pop that open and address them. Thank you for having me. It's so great to be here and it's so great to see all these people participating and tuning in. You know, this is a talk I think that we initially gave right at the beginning of the pandemic and so to come and revisit it is quite something. And to see where we've all come collectively since since that time. So I get one. How do you comment on which is a dominant stricture for any in PSC? I think it's a great question. I think there's a lot of people who sort of have their own definition of what a dominant stricture is. And there's probably something in the literature that really defines it, you know, more effectively, but you know, you just sort of look at it and if there's any stricture usually about a centimeter in its length, you know, that's the one that you start to worry about. It's obviously going to be at the end of the day an arbitrary number because everything starts off much smaller becomes bigger but about a centimeter you start to take notice. And one of the strictures is getting worse if there's increasing upstream dilatation from one of the strictures, not to worry about that one. I think the narrowing itself is, you know, is what it is but you want to look at everything else or I look at the soft tissue if anything around look at the degree of enhancement. And if those features are sort of worse than they were previously, but I think, you know, that's something you need to worry about. It differentiates segmental polypoid thick mobile from polyp on ultrasound. So I don't know if I, if I'm 100% clear on the question certainly you have, you know, gallbladder polyps so that's one thing you're asking and the other is just a little thickening of the of the wall of the gallbladder perhaps or am I missing a specific terminology here. Oh, thick sludge from Paula. Perfect. Okay. And so, you know, you look at the morphology so polyps and we call them pop because they have a polypoid morphology right a little ball appearance protruding into the lumen. And so, you know, you look at all the modalities right so if you start with ultrasound if you see sort of a ball like lesion that's protruding to the lumen we're going to think about it. To be a gallbladder polyps sludge typically layers, but you're absolutely right that you know sludge can have a tumor factor players a tumor like appearance. Usually it's a little bit larger. Usually it's more lobulated in its appearance on ultrasound you're going to put color. And you're going to see if there's flow. You're going to try to optimize it to see if to look for low flow I think even so sometimes it's difficult on ultrasound to pick up really really slow flow. So then you really have to go to MR to differentiate, you know, tumor factor sludge from polyps a tumor factor sludge you know you do a nice good quality MR. You know you're not going to see any enhancement within it. It looks essentially black if you see any degree of gray within it. It means it has some low level enhancements you're dealing with a cancer, potentially a polyp. And those are the sort of things you look for. Another question had come up, I think, in the chat box I'll go there first and come back to the Q&A. When do you use a patability contrast what's your best agent if needed in your opinion. So a patability contrast you know I think the real utility of it there's sort of two utilities usually to help you with liver masses to help you differentiate perhaps an FNH from everything else. Even so there as you may know there's a lot of overlaps, you know, not a lot of overlap but there is overlap and that's some adenoma some hepaticella carcinomas will take up the the agent, you know, you have this in this instance and not excreted. So it'll be hyper intense but the truth of the matter is those are generally uncommon and so if you just want to think about it in practical terms if you have a mass that looks like an FNH and other sequences and takes up the other agent is probably going to be an FNH as opposed to an atypical presentation of an adenoma or a hepaticella carcinoma so I think that would be one good use for a patability contrast agents. Another good use would be our surgeons sometimes like it prior to doing liver resection for for metastases so segment tectomies or you know when they take out individual lesions. They want to delineate every single lesion in the liver and so they use the a patability agent image at 20 minutes to see them as little black holes, so they can really pick up all those lesions and so that's another reason why we use a patability agents. You know, I suppose if you're looking for biolique it's of utility as well and so we've done that a few times sometimes it works. We see contrast come out sometimes we don't actually so there's no harm in trying it. So typically for bioliques, you know, there are enough clues perhaps another imaging modalities and the clinical picture that you can you can figure out it's biolique without having to do a patability contrast, using a patability contrast agent. I suppose the only other thing we use for patability contrast agents is when we are preoperative liver MRs we want to map out the biliria anatomy, and we want to make sure there's no variance, we use our patability contrast agents for that as well. So, let's see what else we have. So two questions on the same topic about differentiating, you know, the mucinocystic liver lesions system, formulose biliria cyst adenomas from simple cyst. Those are going to be very tough, you know, I just in fact we just had a case this morning about how to differentiate when I went through that conversation with my training. And it's going to be tough typically when you look at these hepatic mucinocystic neoplasms they tend to be isolated in the sense that you only see a liver cyst you don't see any other cysts within the liver. So I think about it in that instance you typically you know it's a larger size maybe four to five centimeters borders a little lobulated, maybe a few septations. And so I think and in the right patient population which is typically a female about the age of 50 or above. And so if you see those imaging features isolated cyst lobulated border septations and a female that age group. You want to bring up the possibility of the hepatic mucinocyst cystic neoplasm. Obviously if you see solid components you're going to think of the malignant counterpart. But again, these are uncommon things are common things being common. So just being a cyst that looks a little bit, you know, lobulated and septated but normally I would pass most of those cysts but if it's isolated lobulated borders septations in the right age group. I suggest that possibility. And for those patients they often maybe see a surgeon the surgeon doesn't necessarily take them out and unless the cyst is causing some symptoms. And they'll just follow them maybe at a few, you know, a couple of month interval six months or one year intervals to make sure things are going okay. You know, to use no diffusion imaging and gallbladder and billy malignancy that's a great question, you know, I think if you read the literature you're always going to find folks who write about the utility of diffusion weighted imaging, and in all applications of the abdomen and pelvis certainly with things like prostate I find it essential. Right. And, and even for liver imaging, it can be helpful for pancreas imaging could be helpful. But the honest truth is maybe just our group but we obviously we don't really find it that useful. If you're looking for a restricted diffusion and abscesses or perhaps a malignancy with cells that are packed in together but I have to say, you know, you can probably come up with that diagnosis more often than not, based on the other imaging sequences at the diffusion, perhaps maybe only useful if you don't have a good T2 if you don't have a good post contract sequence and maybe then the diffusion can help but if you have good sequences other than that. I don't know if it helps too much personally to sort of tease out what the diagnosis is. Abnomiosis versus gallbladder cholesterol losses you add no myosis. I think it's sort of a, you know, I once remember reading cholesterol losses was sort of a pathologic diagnosis when you open up the gallbladder and you see all these cholesterol deposits I think it's going to be tough on imaging usually add no myosis. You know, it can be diffused but oftentimes it's more focal as opposed to cholesterol losses which has to be more diffuse but I think differentiating that specifically on imaging I think will be difficult if I recall it might be more pathologic diagnosis that could be wrong on that. Abnomiosis and fundus without ring shadow and how to differentiate sludge accumulation tumor. So I think if you're going to call adenomyomatosis and the fundus you're going to, you know, and you want to call it definitively you're going to want to have all the imaging features of it which is, you know, focal thickening with some polygenic foci which are the cholesterol crystals with the ring shadow. For me if I don't see all of that I'm going to try to get another imaging modality because clearly, you know tumor in that location can can have that appearance and sludge just lying there can have that appearance and how to differentiate that, you know, get an MR MR will show enhancer within a tumor no enhancer within sludge. And so that hopefully can help out in that instance. I'm going to talk about declare impending perforation call better set up to 100cc in volume. Yeah, you know I think that's a, I haven't actually used that term I'm not sure if that's something you use but I certainly think if it's 100cc in volume it's a pretty large call bladder. And so I don't know if I'd use that in my report necessarily you know perforation to me is a binary thing you either perforate or do not perforate it you never know when something is going to perforate. But I may not use that in my dictation but I would certainly call my referring providers say this call but it is really distended and if you don't do something right now. You know it may pop and perforate skin central and peripheral carcinoma occur at the same time you know I haven't seen. Don't recall seeing that happen. I suppose it can, and I suppose you can have, you know, instances of multifocal clangio right happening in the periphery and in the ducks but I don't have numbers on that but it can certainly happen but it's not something that I don't think happens. It doesn't happen that often. When do you say CBD is dilated in young old and post-cholocystectomy patients yeah so I mean I, I don't know if there's updated literature on this but I think most people in our group and when I've gone to conferences talk about, you know, top normal of six and then you add a centimeter, you know, six millimeters for at 60 and then you add a millimeter every decade after that. And post-cholocystectomy you know I've seen so much variety where post-cholocystectomy patients have normal bile ducts or they could be dilated. I think stability is your friend there if it's stable over a period of time you probably assume it's due to the post-cholocystectomy status. If things get worse over a period of time then then perhaps get an MR to make sure there's no obstructing lesion in the ampula. I have a question about 10 minute delayed scan for cholangic carcinoma absolutely if you're worried about a cholangic carcinoma that 10 minute delayed even on a CT scan would be essential so you want to try to modify the protocol to accommodate that. And how to report gallbladder with posterior shadowing. So I think perhaps you're asking about maybe a porcelain gallbladder where you have sort of calcifications and shadowing that's drowning it out. I think it's very tough. I mean if you have a shadowing that's precluding you from seeing the gallbladder you say you know I can't really value it and again you're going to have to get another imaging modality if you're worried about gallbladder pathology. What key features you look for confidently call acute cholangitis on CT and I think it's a great question I mean really looking for wall thickening of the bile ducts as well as hyper enhancement so areas of the bile ducts ball that are enhancing more than other areas if it's all diffusely enhancing then it becomes a little bit difficult but you're really looking for that wall thickening and hyper enhancement to suggest acute cholangitis. If a gallbladder fossil shows posterior shadow how to describe it do we say likely how to like. Yeah I think you're going to have to look at it carefully right so you know if it's clean shadowing it could be you know look for the gallbladder wall echo you know the wall echo shadow complex. If it's dirty shadowing you know you want to be worried about is there some air in the gallbladder wall or is there some bowel gases precluding it. My whole thing is listen if I can't clear the gallbladder because of shadowing. Then you know you may want to get an MR I know I see an MR for a lot of things but you know it is really a problem solving tool and if you're worried about the gallbladder but you can't evaluate an ultrasound you've got to get something else to in order for you to look at it better and that's just this is the way things go. So 10 minute delayed scan only in peripheral congealed on central. No I would get a 10 minute delayed any patients you're looking for a cholangio carcinoma the hyper enhancement a relative hyper enhancement on the 10 minute delayed image will be present with peripheral and central lesions, perhaps it'll be more evident on peripheral lesions because they're more math like and they're embedded sort of have liver parankama that surrounds it so you'll see it a little bit better than in the central ones we don't have that liver parankama around it. But regardless, if you look at it objectively should be prior to on the 10 minute delayed due to that fibrosis within these lesions and so I think that you know getting the 10 minute delay would be essential no matter where you're looking for for cholangio carcinoma. Thank you everybody for your engagement. It's been very useful. And I look forward to to meeting you and engaging with you in the near future.