Pitfalls: Adrenal, Pancreas and Spleen

Objectives of the Presentation

The objectives of this presentation are to present some of the anatomic variants and anomalies of the pancreas, adrenals, and spleen, and some of the benign condition which can mimic neoplasm.

Some of the technical related pitfalls leading to misdiagnose or path pathology or missing diagnosis.

I would not be really discussing a lot about the protocols, because it's very much variable. And that's a whole different subject.

And then changes from surgery, which is always a part of problem in abdominal imaging, in GI and G.

What I will be discussing are really variance of the anatomy in the pan cross some fighting infiltration of the pancreas, fighting imagination, some of the congenital anomalies and which can lead many of them to miss to pseudo neoplasm, adrenal, the same thing basically, and also for the spleen.

Pancreas

Normal Variations and Pitfalls

Let's start with the pancreas.

One of the normal pancreas, when we look at it, in majority of the cases, we expect to see the head of the pancreas laterally to end up into the pancreat cordal artery here. And that's the deum here. That's really the outline of the pancreas laterally, okay? And there is an process going here, and we can see that here.

But in some patients, we see another sort of process, if you will, extending posterior inferior or anterior superior or laterally, basically, and it's about a third of the patients. We see the discrete lobules, if you will, of the pancreas. And that can be a source of misal.

Here is a small arteries, the pancreatic gut artery, and then we can see a piece of pancreas coming inferiorly, or in this case here, we can see that, and this artery here should be our landmark. Anything beyond that could be a normal variation, but that can be occasionally prominent and misdiagnosed for a neoplasm. But the clue is the density of this tissue on all phases of contrast, either early or late, will be the same as the rest of the pancreas. Okay? This is seen in about 10%. You can see that variable percentage in different patients.

Here's another patient. Actually, this was seen a ululation laterally and an MRI was recommended, which really totally unnecessary. It is not necessary to do MRI. You should diagnose this normal variation of the anatomy, okay?

Here is this kind of epigastric pain in a patient who has obviously chronic renal disease. And this prominence of the head was saw and in obviously in a patient with a renal transplant and a lymphoproliferative disorder was suspected. But looking at the density of this is the same thing. Vascular structure is perfectly intact. So there are other clues you really put together as a radiologist. I always say it's kind of pieces of puzzle together. But nevertheless, ANL was recommended, which really doesn't add anything as a T two, weight weighted images, pre contrast, post contrast gadolinium. And you can see there is a normal enhancement of the head of the pancreas without any pathology. So the density really is what matters or the intensity.

Here's another pitfall that we see occasionally. Here is a T two weighted image. We see a small nodule medial duodenum lateral to the head of the pancreas. You can see it on the T one weighted image or on the T two weighted image. But if you look at it, there is a little in the center of that. Okay? You see that here on the T two. So what do you think it is? In fact, this was called a polyp, a denal polyp. Okay? What this is actually is the pule. Okay? It's a normal pule endoscopy. See that here is a drawing of a picture, and here is the little dot that you see, which is really the duct, which is coming down here, and we can see that little dot here. So this is really a normal variation. It is a pitfall. It can mimic a polyp or anything like that. So you don't really need to call it anything because God forbidden. The endoscopies will go in and come out, say, I didn't see any polyp. What do you mean? Okay?

Here's a different type of pitfall in the tail. Again, you can have a prominent of the pale tail of the pancreas. I think sometimes the pancreatic tail may sort of head up a little bit. Sometime it heads down a little bit. It sometimes fold over. See, there are different variations of the anatomy that we see here is the heading down, if you will, wrapping around the kidney, the tail of the pancreas. So these things can happen as a normal variation. So look at the continuous images. Look at the density of the tissue. Look at the enhancement of the tissue before calling it another entity or recommending additional exams or gut forbid a biopsy.

Pancreatic Anomalies

Pancreatic anomalies, you can have agenesis, which is basically incompatible with life. That's very unusual, very. And then we have hypoplasia of the pancreas, which can result of the absence of ventral or dorsal portion of the embryologically of the pancreas, basically. And that partial agenesis of the dorsal pancreas is much more common than the ventral portion. And that leads into a so-called short pancreas. Here you can see that here, the head of the pancreas is there, and we are missing actually the body and tail of the pancreas. So that is not uncommon. Don't mistake that for fatty infiltration, because sometime the fatty infiltration can mask, and we don't see that. But normally we see pancreas extending here as a fat, and I'll show you some examples of that. So that's different than agents of the pancreas, or I'm sorry, or hypoplasia of the pancreas.

Here's another case, hypoplasia of the pancreas, so called short pancreas. See that here, here is the portion of the pancreas. The tail actually is the body is very short. So congenital short pancreas in the 47-year-old female. And that has been described in the literature, which mean associated with polys phal. We can see that here in this patient, which has an additional splenic tissue in where it should be. So that is another entity we should be aware of that which can be a source of pitfall here is congenital absence of the pancreatic head. And we can see that here, the ventral duct here. We can see it. We don't see the head of the pancreas on this CT scan. I don't know why was recommended, but nevertheless, the same thing on MRI, that we don't see that. So that is another urologic abnormality, if you will.

Fatty Infiltration of the Pancreas

Here is the fatty pancreas. Okay? Normally we see the configuration of the pancreas is there, especially when there's a diffuse fatty infiltration of the pancreas. That's not something we should call it a pitfall. It's really just a condition which is seen in certain diseases such as diabetes or cystic fibrosis. And then we have sometimes have the fat infiltration as you see, lobules of the pancreas still there. All landmark here is the splenic vein. Obviously we can see how high it can go into the gastro splenic gas, osteopathic ligament all the way up there. So that's still pancreas up here. So it's really just diffuse fat infiltration, fatty infiltration.

Something of interest has been some reports in the literature, and it can be a source of pitfall. It can have many variations of that, that you can see has been classified into different types of fat infiltration, type one and type two. And as you can see, that's occasionally when we have a fat sparing area, particularly around the ampullar, around the duct, it can mimic a pathology. It can, it's not really a tumor in the pancreas, it's just fat sparing the same condition we see in the liver, for example, fat sparing area. So we can see that area, but occasionally fat infiltration in the head of the pancreas can partially involved the head. As you can see here, the process look like being spared off the fat. And these things has been called two more. Okay? Even I have been cases referred to us for a biopsy, which I generally recommend. Let's do another test. And that's really the best test. You're going to be MRI here is the low attenuation area in the head of the pancreas, out of a sequence gives away, that's a classic focal fat infiltration of the head of the pancreas. This is nothing needs to be done, but even on the CT scan, it would be unusual to have a tumor here without any ductal obstruction, without any vascular change of the caliber or anything like that. So think about fat infiltration before calling it the tumor and recommending biopsy. And if you need to do anything, that really would be a simple MRI if you have to do something else, but that's usually the case.

Now, pancreatic lipoma is rare, okay? But usually that has a distinctive borders or boundaries, if you will. And as a collagen capsule, so that's really not focal fatty infiltration or fatty invagination of the pancreas. That's a small lipoma. We see that's a benign condition. We don't have to be concerned except that there is a rapid enlargement of that. And then you have to think about the malignant conditions for lipos sarcoma. So that's very rare. So it's something, be aware of that. Here we can see it on the T one as a high signal and the out phase we can see as a focal lipoma. Okay?

Now, every low attenuation doesn't mean there's a tumor there, okay? Or there's a lipoma, there's a fat infiltration. Here is a case, a patient who happened to having a CT urogram actually. And post contrast, cortical, I mean the nephro phase, we see that low attenuation in the head of the pan cross and different patient here with the cortico medullary phase. We see that low attenuation here. Okay? Anybody think what it is? Okay, we see the colon here. What is missing here is actually the dual is missing. So if you look at the delayed phase on the CT urogram, there's a contrast in it, okay? On a delayed phase here, there is the air bubble in it. So that's really a sort of, it's an annular pancreas, if you will, annular pancreas, which we see the pancreas tissue all around the DUM here, okay? And as you know, this, normally the ventral di ventral, but rotates clockwise procedure toum to make the, to fuse with the dorsal. But in patient with anular pancreas, that just doesn't happen. As you can see that here, you can see that MRCP on oral contrast, upper GI study, which is usually in pediatric patients who come with obstructive size and then an MRI. So it's really the same thing we see in various modalities. It's in complete rotation of that, the buds that you're talking about.

Okay? As you can see that here, incidental finding, again, the patient with hematuria and the pre and the pre contrast heart to see, except we see enlargement of the head of the pancreas, but we do do contrast because the pancreatic tissue enhances then this annular pancreas, the do within the head of the pancreas kind of stands out on various studies. You can see that here. We can see it on the axial images here on the CT scan. It doesn't matter what you do, it's the same thing, MR. Or CT scan. We don't really need mr. Quite often, we should be able to diagnose on the post contrast CT examination, okay?

There's another patient who mass was seen on ultrasound, on, and by sonography major the size, and then a CT scan was done. We can see that here, the ular pancreas with pancreatic, small rim of pancreas all around that head of that doum. So this thing can be early presentation in pediatric usually. And the later presentation, there is occasionally development obstruction, but quite often we find that as incidental findings.

Pancreas Divisum

Okay? Pancreas divis is probably one of the most common incidental finding, a congenital finding in the pancreas imaging that we see that here. And as you know, that this results from the failure of ventral and dorsal but to fuse, and it's the most common one here. It's in autopsies it is seen about 14% up to 14% of the population. But we do see that on ERCP or MRCP or on multi detect, multi detector CT scanning with sensitivity of about a hundred percent. So if you really look, we should be able to make diagnosis, because quite often these two ducts kind of run parallel to each other. You can see the ventral and dorsal ducts here. Here you can see again the two ducts run parallel to each other. Here is an MRCP, here is the major papilla here, can see the main pancreatic duct comes up here and drains into the minor papilla, as you can see that here, and the common bile duct coming down and merging with the duct from the head of the pancreas and drain into the major papilla here. So that is, it's not unusual really for, I've seen that the CT scans that you read, if you don't think about it, and that's not, that could be important because sometimes these patients, especially younger patient, present with recurrent pancreatitis. So you should be aware of this of this congenital anatomy, if you will, of these patients. So if they happen to go to do ERCP, at least you can tell them that where they really should be injecting to see the main pancreatic duct.

Okay? Here is the patient who happened to have a pancreas divis, and then what is the diagnosis? Absolutely. You can see the so-called prominent pancreatic duct. You can see that here. Some people call it like a snake with the egg inside the belly. And you can see that the whole pancreatic duct due to over overproduction of pancreas pancreatic exocrine function, making a lot of contra, a lot of fluid and it's draining into the minor papilla. The fact it comes here and kind of goes anteriorly, if you will, one clue. But you can see also the pancreatic duct, the common bowel duct posteriorly. So that tells you this is a pancreas in this patient who was further studied by endoscopy. So this was really a dorsal duct IPMN with in pancreas. Mol diver telecom is incidental finding. You really shouldn't mistake that for anything, especially on the CT scan because cut fluid or air in that, but sometimes on MRI it can be a source of pitfall, but usually if you do a T two weight, that usually should you high density fluid. So think about that. You don't really need to do anything else in this patients and especially if they're asymptomatic. So that's something to again to think about it in doing abdominal CT scan.

Other Benign Conditions Mimicking Pancreatic Neoplasm

So among this common thing we discuss about these issues that I'd like to spend the rest of the time talking about, other benign conditions which can mimic pancreatic neoplasm. Okay, let's look at them.

42-year-old man with postprandial abdominal pain. What's your diagnosis? Pancreas. Okay, these are the CT scans. Additional CT scan. You can see the head of the pancreas. There is a dum, there is a low attenuation mass in between with maybe a little cystic changes At the first glance, if you really don't know the history, if you don't know other symptoms, if you don't think about this particular entity that might mention that, Mike mentioned that you will think about a pancreatic neoplasm, but pancreatic neoplasm here without ductal involvement would be unusual, okay? And look like the pancreas itself is okay, here is your pancreas al artery, which tell you that's the end of the head. Basically if you look at this little artery here, you see that here. So this is really, and this pancreas does not have that loation that I talked about it. So if the pancreatic head ends up here with the pancreatic cordal artery as a landmark, what else this could be? Then we are looking at the groove, okay? So the most likely diagnose in this case would be carcinoma group, pancreatitis, al hematoma and lower pancreas. And obviously This patient, different patient is a different patient. Here you can see this was in January and this was in May. About four or five months later, this thing progressed into pseudos formation. And this is classic both cases of groove pancreatitis, okay? It's focal inflammation and fibrosis in the duodenal pancreatic groove, okay? Seen in S who had the Whipple specimen, but this is really an unknown etiology. There's some controversies about what causes that. Is there really heterotopic pancreas? Is there really cystic dystrophy? What is going on in this particular area of so-called groove between the pancreatic head and the duodenum laterally here? So this is really from the literature. So it can be a pure type, which is basically groove in the DU genome and, and sometimes segmental form, which also the head of the pancreas can occasionally get involved. Remember, the pancreas is an organ which does not have a capsule. So not only infiltration of hormone pancreas can extend beyond the pancreas very easily, such as infection or tumor. Things around the pancreas can also involve the pancreas very easily, such as group pancreatitis because of the lack of pancreatic capsule. So you can get that involvement of the pancreatic head in these patients.

Alright, all now how about this case here? Look at that one, another one on MRI, the group between the head of the pancreas and duodenum. So this is something to be aware of that the so-called group pancreatitis, that's a different case from the literature. You can see that again here. Minimal inflammation here with some extending outside anteriorly. Again, a case of group pancreatitis. So this is something I don't really want to emphasize, but we see occasionally, maybe in a very busy practice, two, three times a year, not every day of a group pancreatitis, but one thing you don't want to do is avoiding biopsy or even endoscopy may not be necessary in these patients.

Okay? Now this is one of my favorite case. 80-year-old with history of chronic pancreatitis has undergone an operation. Okay, now you're doing a follow up CT scan. Obviously this patient had a biliary bypass because there is air in the liver, in the bi biliary system in the liver, okay? But then you see this pancreas here, you see a lot of fluid around the pancreatic tissue, Okay? Okay. I mean if you haven't, if you don't think about this entity, you will probably go ahead and biopsy this or drain this or do something which may not be necessary. Okay? I show you more images. You can see that again, the pancreas here, fluid around the pancreas. Pancreas here, fluid around the pancreas. And you can see that on all the images. And this patient actually does not have clinical picture of pancreatitis right now. He had chronic pancreatitis for which he was operated on, but there is no elevation of the amylase or lipase at this time and there is not really significant pain in the abdomen. So what that turned out to be, actually this patient had a so-called al procedure, which what they do, they bring a loop of duodenum and open the pancreatic duct and then basically sew it together here. So the pancreatic exocrine jaw here can drain directly into the duodenum here, into the jun, okay? So what we're seeing here at is the loop of bowel around the pancreas, which is distended and filled with pancreatic juice. That's basically it. Nothing else really. So this is really a postal procedure that we should be aware of that, think about it at least if the patient had surgery for pancreatitis, call the clinician and ask what type of surgery did you do? And he will tell you, oh, I did a personal procedure, I just did the pancreat ostomy, that's what I did. And then you know the answer is what you're looking at here.

Okay? Now moving away from the pancreatitis or fluid collection, there's a mass here we see in this particular patient there's a soft tissue mass, which is here is the head of the pancreas part of that, and there's a mass sitting look like it's either coming from the body, extending cephalad or coming from above extending coda and impinging on the pancreas. Okay? This is, if I tell you this is a piece of the liver, you probably won't believe that, but if you look very carefully, you can see this is connecting to the liver. You see that here? This is basically a pedunculated accessory hepatic lobe. It's a rare condition. I've seen about half a dozen of cases, but something to think about is sometimes they're small, sometimes they're large, but it can happen and usually happens around this area here. And we all have seen angulated hemo hemangioma, we have seen pendulate hepatocellular carcinoma. Why not pendulate accessory hepatic lobe. And are those really the angulated lobe which develop pergio growth in it? Those tumor, I don't know that, I don't know an answer to that, but if you have an old study you can say that obviously whether or not that's the case. But this is really a angulated accessory hepatic lobe which is hanging down here and that these things has been reported in the literature can cause torsion, can cause pain, can infarct and can cause other problems.

Okay? Now, 41-year-old man with weight loss, we do an abdominal CT scan and we found a mast sitting right in the tail of the pancreas on a CT scan. So if we don't know what it is, I know our residents will immediately see anl correlation and some of you may agree with that is recommended, which is finel was done pre contrast T two weighted image a little bit. Hyperintense post contrast look like it's enhancing and enhancing the delayed phase is an arter, this is an arterial phase and that's a delayed phase. So it's your diagnosis. One of the these things here, is this a sero cystadenoma, is this a neuroendocrin tumor? Is this intra pancreatic spleen? Is this an infected pseudos? I wish I put this thing into the audience response so I'll get what percent of you guys get a diagnosis. So which one you want to pick up? Okay, I see many of you pointed to diagnosis, C, which happened to be the case. Obviously, you know, it's not obvious it's a man, a patient. It's probably not the right age group. Usually it's an old, it's a disease we see in grandmothers, hercy adenomas and older women. Usually it's not hypervascular arterial phase. So it's not really neuro induction tumor. There is no history of pancreatitis in this patient and also the spleen is missing sometimes in this patient, but not necessarily, okay? And that turned out to be actually we biopsy this case because we were not as smart as you are to make the diagnosis. So CT guided biopsy provided splenic tissue, which turned out to be the case accessory spleen in the pancreatic tail. Okay? This happens actually after we had this case, this case came first and that's how we learned about this issue. But nevertheless, we biopsy that this the patient arterial phase to a hypervascular tumor in the tail of the pancreas. You can see it on multiple images here from head to toe hypervascular. This was called neuroendocrin tumor and the patient went to surgery and this thing was removed. Okay? So unfortunately this was removed surgically proven, and then we came additional cases. There is a lesion here on the T one and you can see the enhancement pattern on the arterial phase very similar to the spleen because regardless of where the spleen is still it has red and white pulse. So it enhances similar to the normal tissue of the spleen. We can see that here. And if you look at the out of face sequence, it has a so-called Indian ink heart inact telling you this is really pancreatic spleen. Okay? So there are some clues that we can use to make diagnosis of this entity and not biopsying or not doing anything else, okay? If you really have, here's a patient who actually has this spleen, the other patient showed you didn't have this spleen, but doesn't really matter. Here is the best tool that you have five years ago this thing was there. Okay? So you always have look at your old study if you really don't want to do it additional test. So that's your best tool.

Now look at this one here, a small tissue here. You can see that here sitting near the body of the pancreas on various CT images. And then look at the MR regardless of the sequence you use, whether that's the diffusion weighted images, a DC map here on the mr, pre contrast, post contrast, you can see that here, it's the same intensity as the normal spleen regardless of the pulse sequence. You use the same thing here, okay? These are very important really to recognize the same density, the same enhancement of a small accessory spleen, whether that's in the pancreas or peran cross, it doesn't matter. It can mimic a tumor. But remember it is important to know that the patient does not have a cancer. Here is the case. Look at this lesion here near the body of the pancreas. You can see that here on the contrast CT scan. But this patient has a cancer, this patient has a lung cancer. So is it, we're going to call it accessory spleen when you're doing CT scan of the chest for staging. No, we are not. We got to do additional tests and this happened to be a PET ct, which this was biopsied and this was perp pancreatic metastasis. You can see both of them are FDG of it. So what is important is while we like to diagnose perp pancreatic spleen or int pancreatic spleen, think about metastasis in the cancers because pancreas itself can be a target for metastasis in lung cancer.

Mimickers and Diagnostic Pitfalls Around the Pancreas

Okay? Now not that brings me to really a subject of mimickers of diagnostic pitfalls around the pancreas. Let's look at, let's have some fun. Which of these six cases or pancreatic neuroendocrine tumor is that case number one, is that case number two, which have multiple, is it case number three Or so? We have so many cases here of small lesion near or in the pancreas, which we want to make diagnosis of pancreatic neuroendocrine tumor. So you pick up your choice, which one of these cases is pan? I don't think you can tell. Now let's look at them each one at the time.

Here's case number one. There is a fatty pancreas or fat infiltrated and there is a hypervascular lesion or vascular or solid lesion, not hypervascular necessarily, it's a solid lesion, but they look like it's in the pancreas. But in fact, if you look at higher and higher, you may say, well, I'm not sure it's kind of in the proximity of the stomach. Okay, that's exactly what this was. This was a gastric gist. Exo as we know the gastric gist, they can be exophytic and they can get close to the spleen, to the pancreas, to anything. So that's something to think about.

Let's look at case number two. 1 2, 3 lesions, four lesions maybe in the pancreas. So what's the diagnosis in this case? Obviously you all saw nephrectomy spleen falling back here. So this patient had a nephrectomy for renal cell caroma, okay? So these are multiple pancreatic metastasis from a renal C carcinoma, which was removed a year and a half ago. Okay? So these are metastasis, they can be single, they can be multiple pancreas happen to be one of the favorite organs for renal cell carcinoma to go. And I'll show you another example of that later on. So that's very important to make diagnosis of that when you have pancreatic cancer per history of malignancy.

Okay? Now sticking out that, here's the renal carcinoma, here's the pancreas. Do we have a pancreatic metastasis? What is missing here is this is not the right phase for renal cell caroma metastatic workup. You got to have arterial phase because your arterial phase shows that there is a metastasis that you cannot see it here. Okay? This was biased and that changes completely the the staging of renal cell caroma because over here look like the tumor is just locally invasive and still maybe surgical removal is within the gers fascia. But when you see this metastasis, that completely changes a stage four renal sickle carcinoma. Okay? So phase of contrast, cortico medullary versus nephro graphic phase is very important to have the cortical visionary phase. I told you earlier that we don't rely on renal cell carcinoma on cortico medullary phase, but that's why we do both phases, either primary or metastatic workup.

The other case a lesion near the tail of the pancreas, very similar to the spleen. So this is the classic picture of spleen wall that should not be a problem related to diagnosis.

Okay, what about this one look like a shape of a heart, very vascular lesion. Now if you have multiple images, obviously you do all kinds of things including map and treaty reconstruction and vascular mapping. So this is really a splenic artery aneurysm, which is projecting down and bouncing into the pancreas in and out, compressing on the pancreas. So it's not really in the pancreas, it's just pushing on the pancreas.

Okay, what about this one? This look like a vascular lesion. This look like an arterial phase. Relatively not the early arterial phase, maybe late, okay? This is actually what turned out to be our pancreatic neuroendocrine tumor, okay? Quite often these lesions is picked up by endocrin, by endoscopies, by gastroenterologists who will do the endoscopy and see this directly by putting the scope inside the stomach, they can see this lesion right here in the pancreatic tissue, okay? And then for some reason angiography was then showing the hypervascular tumor in the body of the pancreas. So that is a pancreatic neuroendocrine tumor. Okay?

What about this one? This was biopsy. This actually is a ectopic pancreas. Ectopic pancreas, which can happen in the stomach, can happen in the proximal small bowel, particularly in the duodenum. That can be a source of misdiagnosis for other entities.

Okay, let's look at this case. I'm going through your several images on this as we move down. And then you look at it, see what, what you think it is. What is this? So what's the best diagnosis of this lesion? Is it an endometrioma? Is it a carcinoid? Is it an ectopic pancreas or that's osis? Say it again. Yes, somebody mentioned that looked like a loation. Very similar to the pancreas right here. Very similar. Okay, that's exactly what that turned out to be. An ectopic pancreas, which was biopsied by endoscopies. So again, look at the tissue, look at the density of that, look at the loation of that normal spleen would not have that loation. The endocrine tumor would have much more degree of enhancement compared to the normal pancreas. So that this, this is what that turned out to be. The heterotopic pancreas is really incidentally about two to 5% of the autopsies. We see that here, usually asymptomatic and you can see it can happen in the stomach and doden here. And there are case reports on other parts of the body, which is extremely rare. Cases I have seen usually are in the proximal gi.

Now this is a case, which was given to me by a very good friend of mine, 55-year-old man with epigastric pain. There is a soft tissue mass in the tail of the pancreas and anybody wants to make the diagnosis. Well, is it an adenocarcinoma? Is it an endocrine tumor? Is it a autoimmune pancreatitis or it's a lymphoma? Okay, obviously adenocarcinoma. Look at the splenic vein. You really see that it should be in case and obstructed in adenocarcinoma and would not have such a well-defined border. It's not vascular, obviously it's an arterial phase. Mr T one. And could this be autoimmune pancreatitis and lymphoma? Possible either one can be the case. Obviously lymphomas generally don't encase the vessel, okay? But what you do, you do IgG four, just serum analysis. Okay? Unfortunately this patient went to surgery and this turn out to be histologically proven autoimmune pancreatitis. So that wasn't really a necessary to be done. Very nice article written on autoimmune pancreatitis, which I highly recommend you to read that because that's a very important topic to be aware of that because we do see cases.

Here's another case. I saw the UCI about six months ago, okay? And a young patient, young patient with nausea and vomiting. There's a soft tissue mass in the tail of the pancreas, okay? And we can see that here on the delayed phase, it is not really seen clearly. So this is another case with the elevation of IgG four to be autoimmune pancreatitis. Classically we see autoimmune pancreatitis as a sausage shaped pancreas. You can see that here with halo around that. But that's not always the case. It's not always happened like that. This patient was treated. You can see that few months later everything is gone to normal on this patient with autoimmune pancreatitis. Unfortunately this wasn't the case in this patient. 67-year-old with abdominal pain, you can see there was a mass detected in the head of the pancreas. MRI was done. And you can see the mass was major to be about over three centimeter in size. MRCP shows there is obstruction of the common bile duct distally obviously, and that's why a diagnosis of cancer was made and the patient went to a ripple surgery and patient pathology was autoimmune pancreatitis. So you can see your pitfalls can lead to a major surgery. I mean Whipple surgery is not a simple surgery. The scar would be carried with the patient for life. So you really don't want to have that situation happens. We learn our lesson from those cases that when we saw this case with a little bit warm here on the T two weighted image, a little low attenuation here, maybe mild abdominal pain with the let's do the G four. And that was elevated actually and that turned out to be, can see 270 milligram per deciliter and that turned out to be an autoimmune pancreatitis.

So there are many articles literature, Japanese are the one who described this entity actually, but there are many articles in radiology as well as GI literature topic talking in this topic about elevation of the IgG four, its specificity. There are extremely rare cases of pancreatic cancer has been described. I really recommend to look at this article. It's a very nice article which I have put the summary of that here, which have some cases of cancer reported with IgG four, but that's extremely rare comparing to autoimmune pancreatitis, which I don't have time to discuss that.

Adrenal Glands

Okay, now let's move to the adrenal glands. We have about less than 10 minutes to cover adrenal and spleen and I will try to discuss.

You can see adrenal gland, you have to see a hundred percent of the time you see it on MRI or a CAT scan. Doesn't matter what you do, you got to see them, okay because it's anatomic landmark is very clear, okay? And you can see it's vascular supply and venous drainage is very clear. One vein on the left side, one vein on the right side draining into the IVC draining into the renal vein. Okay? And it's shape is variable. You can see that here come come a small line all the way to the Y shape or inverted y shape. And you can see the drawing here shows many configuration of the, and sometimes even we can see it as a small triangular shape on the left side particularly which has concave borders. Okay? We cannot see the medullary and cortical portion of the adrenal gland with our current modalities. However, I've seen occasional very good dynamic CT scan which the cortex enhance a little bit more than the MedU law, but that's not really an issue that we need to discuss.

Okay? In pediatric infants, the adrenal glands are usually larger than older patients or even older children be maybe because of the hormonal effect of the modern maternal hormonal effect maybe. But we see that often as a large adrenal gland that's not considered to be pathologic.

Okay? Adrenal pseudo tumors including hematoma, infection of the adrenal gland, non-ad anatomic variations or structures around the adrenal gland, adrenal benign lesion in a cancer patient, they all can be a source of diagnostic pitfall. Hematoma, there is always a history of trauma usually happens on the right side because the adrenal is sitting between the liver and the spine. More common to see trauma here, but you can result as of anticoagulation, sepsis and other things can cause adrenal hematoma. So that's really should not be a problem. We can see bilateral adrenal in the patient who was anticoagulated hematoma. Again, this is not really a tumor. We can see the vessels normally going through that adrenal vein here. So that really should not be mistaken and simply a follow up will solve the issue. History and follow up would solve the issue. Okay? MRI can tell you if the patient has recurrent bleeding, different phases of hemorrhage basing at what age is the hematoma, the signaling intensity would be variable as you are well aware from your neuroradiology experience.

Okay? Now this is the patient, 26-year-old remember AIDS patient malaise, loss appetite, everything pointing to basically there's something wrong. We think about lymphoma in AIDS patient also, we have to parallel to that to think about infection. Okay? Mass was seen in our general gland here, we can see that here. And then for which a CT scan was done, pre contrast, post contrast, we saw it's bilateral not only on the right side as was taught here on the, on the, you can see adrenal gland here behind the IBCs, our landmark. Okay there we can see that here behind the IVC. So there is a mass bilateral, we didn't know what it is at this stage MR was done. You can see various pulse sequences here. The density really changes a little bit the intensity here, but nevertheless we don't have significant enhancement, heterogeneous enhancement on both sides. Post contrast, you can see on this coronal T one weighted post contrast images. So because of the history of aids we talked about possibility of infection and then a biopsy proved this to be al histoplasmosis actually, which is supposed to be the cause of original insufficiency in immunocompromised patients. So think about that when you look at this patient with that kind of history infection.

Now this is one of my cases that you probably see a few times in a year, but that's not important in a non-cancer patient. A cancer patient can be important because when you see a mass sitting right in the adrenal fossil on several CT images, think about this connection with the stomach. Okay, this patient has assist your lung cancer and was evaluative for pulmonary embolism. Actually you can see the arterial face but this an abdominal upper, upper abdominal images showing the soft tissue mass. You can see the adrenal gland is normal actually you see that adrenal gland is seen both lateral and medial limb looks perfectly normal. So this is really a gastric diverticulum, gastric diverticulum which projects in that area through a defect in the posterior paral peritoneum. And you can see in the letter drawing sometime we have, we are lucky because we can establish the communication of that and sometime there's a little air bubble inside it. So this may be easy to make diagnosis but not all the times. So think about it, if you need to do additional tests, use oral contrast to opacify it because you may be able to o pacify it. Turn the patient prone before recommending a biopsy. Look for the adrenal gland on thin slices.

Okay, what about this one here? Non-contrast CT scan and nodule in the adrenal area. But look at the post contrast. This is really a neat case of a patient with portal hypertension has collaterals and one of the collaterals really coming out here beyond the liver capsule. Interestingly connecting with the gland and draining into the IVC. Okay? So it's really an adrenal pseudo lesion. It's a slen renal slen. IVC shunt if you will, I'm sorry, portal systemic shunt portal systemic shunt from the portal vein into the systemic blood circulation through the adrenal area here. Okay, here's the patient with the pancreas actually projecting into the adrenal fossil and mimicking a pseu lesion. So all kinds of things can happen. Pancreas vein, spleen, spleen. Look at the enhancement pattern and post gadolinium heterogeneous enhancement because of red and white pulp, again mimicking in adrenal lesion. Okay, slen.

So common facts about the adrenal gland basically is adrenal nodules are common, often discovered on CT and MRI. Adrenal nodules are almost always benign, often a non-functioning abnormal but they must be characterized in the cancer patient, okay? Adrenal is a very common site of metastasis, okay? But in a non-cancer patient you have to think twice before recommending additional tests. And this patient, especially when they're small and homogeneous, every effort is made to differentiate this common condition from less common malignant lesion. And that's really why there are so many articles written on this emphasizing the value of CT scan basically in this patient. What we use here nowadays for our general lesions is the size density enhancement, the enhancement. That's really what all you need. You don't really need MRI or PET in this patient and if it's done, it's done. Incidentally for something else, I think we should be able to make diagnosis on this. Non-contrast ct, especially the delayed, okay, so the size is number one obviously in this patient what we look for, but we got to look at the patient clinical picture. This patient actually was hypertensive and they were looking for aloma. This turned out to be a small Aldo Sonoma in al gland. So the size is important and when we say nodules of one centimeter or less or negligible, but not in a patient with abnormal endocrine profile, okay, here is a patient which has no clinical symptoms. It's for total incidental lesion, very low attenuation lesion. And that brings that to the subject of attenuation value of these patients. You can see the lower the attenuation value, the higher the specificity to be a benign adrenal abnormal, a benign adrenal abnormal, particularly lipid rich abnormal we're talking about.

Okay? Then we are looking at the contrast enhancement that you must do. Delayed scan 10 minutes has been recommended. Mostly you can see it goes from 70 or 80 to 20 or 30 hands. So that's practically home run. You don't need to do anything else after this in a patient. Okay? Here is a patient actually who had MRI. We can see on the post contrast there's a small nodule here which happened to be an adenoma containing fat which has metastasis in it. Okay? So those things usually have a different enhancement pattern on CT and MRI. Okay? Or signal intensity I phase and a pulse phase that we will basically give it away and or or isotope, which practically we don't really need all of these things here. We can stop at this point for our adrenal lesion.

Here's another patient with lung cancer. Look at that here. There is out phase, you can see on the post contrast actually here fat containing adrenal nodule has a nodule enhancing nodule inside it on the T two or on the post gadolinium, you can see enhancing. This happened to be a collision lesion. Here's an auto face showing fat tumor fat. So it does help whether just contrast CT scan or M or vin MRI probably not because CT scan should really tell you this is a nodule, this has to be biopsied. So this was targeted biopsy trans hepatic and turned out to be metastasis in the preexisting abnormal.

Spleen

Okay? Now spleen, which I'm going to spend a couple of minutes talking about that is a normal variation. Basically enhancement pattern can be a source of pitfall but you generally, we recognize that on the delayed phase because of root pulp and BiPAP polys, phia is not really a problem. But accessory spleen can be a problem, especially when it happened to be unusual location which can lead to that biopsy should be very careful. Look at the enhancement pattern without recommending biopsy. Here is the enhancement pattern arterial phase which can mimic infarction, but you can see it's gone on the delayed phase. So it can have many features on the contrast. Enhanced lobulated spleen, trust me, this patient, we call it lobulated spleen arterial phase shows a difference in enhancement maybe because blood gets there a little different time than this one here and but the delayed phase they all the same thing. Okay? But MRI was recommended still we called it liability spleen but we were twisted hand by the surgeon to biopsy. It was biopsy that turned out to be normal spleen. So I think the MR on the, especially on the A DC map showed you the similar signal intensity.

Okay, I talked already about the intra pancreatic spleen. You should not really have any problem with this. All study is the key in this patient. You can see that here. CT two years earlier shows intra pancreatic spleen, okay? And then accessory spleen can happen many places. Normal spleen is there but there is an accessory spleen here. Look at the enhancement pattern on MRI. Very unusual location. We did not call this, this actually went to University of Michigan, was removed surgically and I had to call the pathologist, they call it an accessive spleen. I've never seen that in that location, but that's what it was.

Now the accessory spleens can be a source of a problem. Here is a patient who has accessory spleen, normal spleen came to the ER with acute abdominal pain. You see that here. And this turned out to be actually a pedunculated accessory spleen which has forced in the lesser sac. I saw this case. And then we saw this case a few couple of years later, 24-year-old patient present in the ER with the soft tissue mass in the pelvis and ultrasound on CT scan, urinary bladder, hypo coic mass. We biopsy that. The surgery called me the pathology called me and said well I'm looking at the necrotic spleen. Then we went back and did the reconstruction images and we saw this is an accessory spleen actually and a long pedicle coming down into the pelvis and that went to surgery was removed and actually that was a torsion and infarction of an accessory wandering spleen. But look at the thickness of this pedicle thin here and thicker. And that's exactly where the torsion has taken place inferiorly. So this thing can happen but be aware of that before calling it something else. And actually we did biopsy. We did not make a prospective diagnosis in this case.

Okay, now this brings up the right time to show this case as a companion case. Very rare spleen epidemic and testicle. Okay? And when you do MR and CT scan, you can see this. The whole thing is connected. Believe it or not. This is all splenic tissue. This is all splenic tissue. You don't believe it. You do a nuclear medicine study and that tells you this is all splenic tissue coming down here. Okay? So this is another very rare condition, so-called splenic AL fusion, which is congenital has been described in the literature but again can be a source of pitfall particularly in the ultrasound exam. Congenital anomalies, many wondering spleen, nuclear medicine is probably the key to make the diagnosis. Again, I'm running out of time. They can cause torsion and infarction of the spleen in this patient. You can see that here. Multiple poly spleen obviously is usually associated with other anomalies such as the azygos continuation of the IBC for example. You can see that here. So those should not really a problem for a pitfall, for a misdiagnosis of a neoplasm.

I already showed you the short pancreas in the patient, which can be associated with polys. Nia here is a short pancreas. That's all pancreatic tissue you have. But look at that spleen here, spleen here, spleen here. I mean there's everywhere there are. This patient has multiple splenic tissues here, here, here. And there is also a short pancreas here with a slight prominent duct. So this is also an association, which already I told you has been described in literature.

Osis is a totally different issue, always associated with trauma, history of trauma when the splenic fragments implant all over the peritoneum. You can see that here. And then you should not be mistaking that for a metastasis. This patient had again, splenectomy, multiple small splenic tissue all over the peritoneum and look at that lateral to the liver. Look at that sometime, maybe even in the liver has been described. Okay? And these things can be specifically diagnosed by nuclear medicine examination Osis osis.

Okay, splenic tumor. I don't really have time to talk about it. There are many tumors in the spleen. The most common one in he angio cyst and then lymphoma and other things such as metastasis, but nothing else.

Okay, I'm going to finish up with this case. Okay, look at the CT scan. This patient has a small, is a large lesion in the liver, an ultrasound echogenic. But the key diagnosis really is the MRI, which diagnosis was made because on the contrast enhancement, that is heterogeneous enhancement. But when you do a out of face sequence, you can see these things is dark and that show you there is HemosIL in deposit in the patient with extramedullary hematopoiesis.

Conclusion

So the closeup, again, I show you this slide, which radiologists basically has should have a knowledge of anatomic variation, medical surgical history, the same thing as I mentioned earlier in the pancreas. Protocol is very important. I'm sure they would be emphasized on that oral and IV contrast. Okay? Timely injection and timely ingestion if you will. And then think about benign conditions and pitfall that we discussed. Thank you very much for your attention.