all right so we're going to start on the liver the first thing is that you want to make sure that you are oriented on this model you want to make sure that you know your rights and left because a lot of these structures are going to be named based off of right and left so the first thing i look at is the size of the lobes okay so the size of lobes are going to tell you exactly which direction you're looking at so for example the right lobe is going to be bigger than the left lobe okay so again this is the right lobe this is the left lobe right lobe is going to be bigger in size okay in terms of anterior versus posterior the anterior side of this model is going to have the gallbladder peeking out okay so again the gallbladder peeks out from the anterior side and then the ivc the inferior vena cava is going to poke out from the posterior side of the model okay again this is going to be our ivc okay so now that we've identified right versus left let's go ahead and talk about some ligaments that we can see from this view the first ligament that we can see is going to be our right coronary ligament okay so again that is going to be our right coronary ligament it doesn't really have much to do with the heart just so you guys know so then the right coronary ligament is going to transition into your right triangular ligament again that is going to be your right triangular ligament the left side does the exact same thing so this is going to be our left coronary ligament again that is our left coronary ligament which eventually becomes our left triangular ligament okay left triangular ligament now the ligament that comes down the liver and it seems like it's separating the right and left lobe that is going to be called our falsiform ligament or falsiform ligament so again this can be called our falciform ligament and i always say the falsiform ligament or falsiform ligament falls down the liver okay so again the falsiform ligament falls down the liver okay now if i were to tilt the liver back up you guys can see a change in coloration between these two sides and they do that for a reason and it's to show a region in the liver known as the bare area okay so all of this in this brighter red color is going to be the bare area and it's called the bear area because there's something known as your peritoneum that actually covers essentially all of your gi organs and the one spot on the liver that is not covered by that peritoneum is going to be called the bare area and a lot of that is because the liver is in such close proximity to the thoracic diaphragm okay so then i'm going to flip the liver over from this side i know this looks really scary but i promise it's not the first thing i'll identify is the right lobe and the left lobe so again it gets a little confusing because the right and left actually flips on this side but from here we can also see the caudate lobe okay again that is going to be our caudate lobe okay and the way that i memorize the caudate lobe is if you guys remember the ivc was towards the back of the model right so caudate means our or caudate is similar to caudal and we know that caudal means towards the back or towards the buttocks right towards the posterior side okay so remember caudate it's on the back okay the other lobe is going to be pretty easy to memorize as well it's going to make a square shape that is going to be our quadrate lobe okay so again that is going to be our quadrate lobe okay and then from here we get to what might possibly be the three most important structures of this block let me zoom in a little bit so these three structures right here in the middle of this model these collectively are going to be known as the portal triad okay again these three structures collectively are going to be known as the portal triad you absolutely 110 percent need to know what three structures make up your portal triad you'll see them a lot on our pancreas models as well so that will come back but anyways so i'm going to go ahead and talk about each structure one by one the first one the largest structure here in purple that is going to be our hepatic portal vein okay so again that is our hepatic portal vein and also just for background for context hepatic means liver associated okay so next to our hepatic portal vein we are going to have our hepatic artery proper okay again that is our hepatic artery proper okay you guys should see that again on the pancreas model and again more of the blood flow uh that uh gives off the hepatic artery proper will be shown on the pancreas so i'll let whoever does pancreas talk about that uh but from here in green we're going to have the common bile duct okay anytime you guys see dark green on this model think bile associated so again that is going to be our common bile duct um so you guys are going to learn uh about another type of circulation known as portal circulation okay now i will leave the majority of the information with portal circulation to dr dao but just to give you guys some basic background knowledge one of the main jobs of the liver is to cleanse a lot of the blood that actually flows through your gi tract okay because as blood flows through the gi tract it tends to pick up a lot of toxins right so all that blood coming from the gi tract is going to drain through your mesenteric veins which you guys also have to know for this block and the end goal of those mesenteric veins are eventually to drain into the hepatic portal vein okay so then that hepatic portal vein is going to send all of that blood through the liver where that blood can be cleansed of toxins okay so that's the main job of the hepatic portal vein now the hepatic artery proper has to do more with your systemic circulation so obviously the liver needs its own blood supply to be able to function properly so that's where it's going to receive its supply of oxygenated blood okay and then we'll talk about bile in just a second okay but anyways so all that blood that is being delivered to the liver either through the hepatic portal vein or the hepatic artery proper that blood is eventually going to be drained in through these blue structures okay these blue structures are going to be known as our hepatic veins okay so not our hepatic portal veins are just our hepatic veins okay so if we were to pin anywhere here in blue we would want hepatic veins now another good view of the hepatic veins can actually be seen from this view so these are going to be our two hepatic veins here we have one for the left side and one for the right side so again if you know the size of the lobe you should be able to guess right versus left this vein going towards the bigger lobe would be our right hepatic vein so again that is our right hepatic vein and then this is our left hepatic vein and again that is our left hepatic vein okay the hepatic veins are going to drain into our inferior vena cava right so again just repeat that the two hepatic veins are going to drain into our inferior vena cava okay alrighty um so last two things before i talk about bile there are two fetal remnant structures that are actually going to be potentially on your exam you guys have to know both the post fetal name and the fetal name however just like with the heart model assume unless we specify otherwise that we're talking about the adult structures whenever we pin these so the first structure here on the bottom is actually going to have two different names one name for this structure is going to be the round ligament of the liver okay again round ligament of the liver and we have to say of the liver because there is a round ligament of the uterus the other name for this is going to be our ligamentum teres so round ligament or ligamentum teres in fetal life this is actually our left umbilical vein okay so again those first two names that i mentioned were post fetal the left umbilical vein is the fetal name for this structure okay now going up top the post fetal name for this structure is going to be our ligamentum venosum so again that is going to be our ligamentum venosum the fetal name for this structure is our ductus venosus again the fetal name for this structure is the ductus venosus all right so basically just to give you guys a really short explanation as to why we need each one so the left umbilical vein actually takes blood from the placenta and helps deliver it over to the fetus now we need a way to bypass all of this liver circulation kind of like how the ductus arteriosus uh tried to bypass pulmonary circulation right so that left umbilical vein is going to take that blood send it over to the fetus and it's going to be shunted straight to the ivc by that ductus venosus okay so again the whole goal of these two is basically to bypass liver circulation okay so from here we can start talking about bile so i want you guys to at least know why we need bile so really the main job of bile is to break down fat through a process called emulsification all right you guys do have to know the different pathways that bile can take through the liver so i'm actually going to remove this model real quick and show you guys this little flow chart let me zoom out just a bit okay now i know it's not the most sophisticated flow chart but it does get the job done lindsey and sebastian are more of the artistic ones in the group but anyways so bile is going to be produced in the right and left lobes of the liver and that bile is going to be transferred over to the right and left hepatic ducts okay the right left hepatic ducts now the bile coming from these ducts are eventually going to merge into the common hepatic duct okay so again the bile coming from here merges into common hepatic now from here the bile can take one of two destinations if we need to use that bile right away it can travel through the common bile duct which i showed you guys in the portal triad and then that common bile duct is going to send that bile over to the pancreas and you guys will learn more about where that bile goes once you actually get to the pancreas model okay now let's say that we don't need to use that bile right away instead let's say that we would like to store that bile we can actually send that bile from the common hepatic duct over to the cystic duct okay so instead of going to common bile we're going to send it over to the cystic duct now from the cystic duct we then send that bile to the gallbladder which i showed you guys earlier and that bile is going to be stored until we need it for further use okay so again notice that i drew two two-way arrows here so keep in mind that this pathway has to go two different ways obviously because we have to have a way to utilize that bile if we need it so let's say that we eat a meal that for example is very high in fat we need some additional bile what happens is eye cells in the duodenum are actually going to and eye cells are short for intestinal cells by the way eye cells in the duodenum are going to detect that we need additional bile and they are going to promote the secretion of something called cck okay i believe the full name is cholecystokinin or cholecystokinin i'm not going to write out that whole name so i'm just going to say cck so once that cck is secreted it's going to cause the gallbladder to contract and then once that gallbladder contracts that bile is going to send or that bile is going to travel back up through the cystic duct and then here and through the common bile duct okay so maybe i should have drawn those arrows going over here but again just to emphasize this the gallbladder cck is going to cause contraction of the gallbladder it's sent back up through the cystic duct and then from the cystic duct that bile actually then heads over to the common bile duct okay so i'll actually draw we're going to scratch this i would say this is more accurate okay cool alrighty so let's go ahead zoom in just a little more so you guys can see okay so i will do my best to show you guys clearly where each duct is i apologize if it's not entirely visible but the right hepatic duct is going to be here so again that is the right hepatic duct the left hepatic duct would be here so again that is the left hepatic duct these two ducts are going to merge into the common hepatic duct so again left and right merge into common hepatic the common hepatic can take one of two paths if we need to use that bile right away we can send it straight to the common bile duct so again that's the common bile duct however if we want to send that bile over to storage then that bile is instead sent to the cystic duct okay that bile is instead sent to the cystic duct and then from there bile goes to the gallbladder again two-way pathway cck causes gallbladder contraction from there that bile can be sent back up through the gallbladder back up through the cystic duct and instead that bile then travels back up through the common bile duct where we can use it okay and that is it for the liver all right so this is going to be the pancreas okay so the pancreas is going to be one of these accessory organs that food doesn't necessarily travel through but the effects of the organ actually have a great deal on the food as it travels through what we know as the gi tract okay so the pancreas is super cool because it not only does it have those exocrine functions okay exocrine meaning it's dumping chemicals um through a duct okay it also has endocrine functions which means it's dumping those chemicals into the bloodstream for to have an effect kind of later on through the body okay so the exocrine functions of the pancreas are going to be secreting things like pancreatic enzymes as well as sodium bicarbonate okay those are going to be secreted and eventually get to the duodenum okay and that's going to help affect and help the digestion of the chyme okay the endocrine functions are what you probably have heard of as insulin and glucagon that whole relationship right so if the blood sugar in a patient is really high right the pancreas is going to secrete the insulin from its beta cells in order to reduce or have these cells of the body increase their glucose uptake to reduce the total blood glucose levels okay from the alpha cells in the pancreas we're going to have glucagon secretion which is say in a patient that has low blood glucose it's going to send it to the liver um in order to secrete um more of the stored glucose in the body okay in order to raise the blood glucose okay so we talked about some of the endocrine and the exocrine functions of the pancreas okay so let's kind of start naming some of the structures all right so not all of this is actually the pancreas the pancreas is actually sandwiched in between two other organs we can see right here okay so on one end this kidney-shaped structure is actually not the kidney it's rather the spleen okay so what the spleen is responsible for is uh filtering out and kind of destroying old blood cells okay so it filters the blood and destroys the old unhealthy red blood cells all right on the other end opposite to the spleen we have the duodenum okay so the duodenum is that initial part of the small intestine where the chyme from the stomach is going to dump into right the duodenum and then continue down through the jejunum and the ilium eventually dumping into the large intestines okay so this is the duodenum we can see here okay the pancreas is going to be what is this chewed kind of bubblegum looking portion sandwiched in between both the duodenum and the spleen okay so a few different parts of the pancreas we can see is that the head of the pancreas is this kind of larger portion kind of in the crook of the duodenum the body is going to be everything up to this point whereas the tail is going to be what is kind of connected to or attached close to that spleen okay so tail of the pancreas head of the pancreas all right and then all the stuff kind of in between is the body of the pancreas all right um so the way that those uh pancreatic enzymes and that sodium bicarbonate are dumped into the duodenum is through initially these pancreatic ducts all right so we see two here we have this nice big one which is the main pancreatic duct okay the main pancreatic duct and then the smaller one which is called the accessory pancreatic duct all right so the main pancreatic duct all right is going to eventually dump into this little hole right there which is called the major duodenal papilla or papilla okay so the contents are going to go through they actually go through another structure that we're going to talk about in a second we can't see because the model is blocking it all right it goes through this kind of swelling and then eventually through the major duodenal papilla which is this hole okay again dumping its contents into the duodenum all right this accessory pancreatic duct which you can see here is going to dump through this other small hole called the minor duodenal papilla okay so the main pancreatic duct being that nice long one dumping through the major duodenal papilla and then namely the accessory pancreatic duct dumping through the smaller one which is the minor duodenal papilla okay so i mentioned that there was a structure kind of between the main pancreatic duct and the major dual papilla okay so you can't see it here again it would be in this general area but it's called the hepatopancreatic ampulla or the ampulla of vader okay and i'll actually show you a drawing of that right now okay guys so this is the drawing that i just promised to show you okay and we were just talking about a structure that we uh can't see on the model but lies between the main pancreatic duct and the major duodenal papilla okay so that structure is going to be this guy right here right which is the ampulla of vader or the hepatopancreatic ampulla okay so the definition of an ampulla is going to be a dilated portion of a duct okay so we have the main pancreatic duct and let me do a little drawing all right or draw over the drawing at least all right we see at the end of that duct right we have this little kind of dilated portion okay so that dilated portion is going to be the hepatopancreatic ampulla or that ampulla of vader okay so you'll notice that it kind of has a few little passageways that dump into that hepatopancreatic ampulla okay one of them is going to be from the main pancreatic duct right we just saw there dumping that sodium bicarbonate as well as those pancreatic enzymes okay so again those pancreatic enzymes or that sodium bicarbonate will dump into that hepato pancreatic ampulla okay we also have kind of another passageway okay and this is actually going to be coming from the liver or the gallbladder all right so we have a bile which is produced in the liver or stored in the gallbladder coming down all right through the common bile duct and then eventually dumping in to that hepato pancreatic ampulla as well okay so we like to think of this hepatopancreatic ampulla is kind of like a blender okay so it's gonna mix all of these right enzymatic juices right it's going to mix the bile it's going to mix the pancreatic enzymes it's going to mix up that sodium bicarbonate okay to make this nice kind of like slushy of juices okay from there when ready it's going to be secreted through the hole which we already know we saw it on the model called the major duodenal papilla okay so what we can't see on the model let me erase the rest of this stuff for you all right so what we can't see on the model is a little guy represented by that star right this little swelling right here which is going to be that hepatopancreatic ampulla or that ampulla of vader all right and then again remember on the model it's going to be located between that main pancreatic duct and that major duodenal papilla okay okay so this does also give us a um good representation of that biliary tree right so gabe when he was talking about that liver model talked about some of these ducts that eventually form the common bile duct okay and these are kind of the passageways that the bile takes to get to either the gallbladder or to that hepatopancreatic ampulla right okay so remember that bile is going to be produced in the liver okay but is going to be stored in the gallbladder okay so remember that gallbladder doesn't produce bile okay so hopefully you remember from the liver segment right that from the liver we have a left and a right hepatic duct okay those come together to form the common hepatic duct okay so from this point right the bile kind has two options it can continue down right to get to that hepatopancreatic ampulla to mix with those other juices to eventually get dumped through the major dual papilla into the duodenum or the other option it has is to go back up the cystic duct right to be stored in the gallbladder okay so this kind of whole system is called the biliary tree okay we did see that with the liver okay so now that you've seen kind of the structure that is in between you know that main pancreatic duct and that major dwelling papilla all right you understand kind of the pathway that those uh chemicals take okay so through the main pancreatic ducts all right we get to that uh hepatopancreatic ampules remember that kind of swelling ampulla again refers to sort of a dilated portion okay so you have that swelling or that dilated section right here where those pancreatic juices all right those pancreatic enzymes are dumped into all right then we remember we also have the common bile duct dumping into that uh hepatopancreatic ampulla or that ampulla vader okay where it kind of mixes up all those juices where it is eventually going to be dumped through the major dual papilla into the duodenum okay so i hope that makes sense okay for the sake of this model all right so realizing that we can't pin specifically the hepatopancreatic ampulla or the ampulla evader because again it's hidden right around here what we would do is we would take our pin and put it inside the hole okay so if you see the pin the tip of the pin inside the hole it's referring to not only the major dual no papilla but what is inside just behind that major dual no papilla which would be of course the hepatopancreatic ampulla or that ampulla of vader all right so again if the tip of the pin is inside that major dual papilla that hole it would be the major duodenal papilla the hepatopancreatic ampulla or the ampulla of vader okay important to note that surrounding the hole so if the pin was on the outside of the hole that would be known as the sphincter of odi or the sphincter of odai okay that's referring to the structure surrounding the hole okay again a sphincter kind of restricting or allowing those pancreatic juices and other enzymes to flow through right that major dual of a pillow okay okay so we talked about most of the structures on the pancreas but what we need to talk about now is going to be the blood flow okay so from this anterior view we can't really see a lot but we can see a few of these vessels but i kind of want to start by turning it up okay so this is going to be the top of our pancreas okay so if we remember um sort of in that gi overview video we have the stomach sitting right above that pancreas okay where the stomach contents are going to dump through that pylorus right into that duodenum all right so we have the stomach kind of sitting above the pancreas okay so this is going to be the superior portion of the pancreas okay this vessel right here all right this guy that is going to be the first branch off of the abdominal aorta all right so this is the first branch of the abdominal aorta hopefully you know or if you don't know it's all good it's called the celiac trunk okay so that first branch is going to be the celiac trunk okay easy way to remember the three main branches off that abdominal aorta is going to be remembering the pneumonic csi so we have the celiac trunk as the first one then the superior mesenteric artery as well as the inferior mesenteric artery okay but again the first one we're talking about is going to be that celiac trunk that celiac trunk has three branches and those are going to be the three we're going to talk about okay so again this guy would be the celiac trunk this first branch all right is sticking straight up going to the organ that sits above the pancreas right and we just talked about that's going to be the stomach okay so this artery is called the left gastric artery and it's going to run up and supply blood to the lesser curvature of the stomach so along with that lesser curvature of the stomach right that left gastric artery which again is right here also supplies blood to um some of the lower esophagus as well okay so that's the first branch off that celiac trunk okay the left gastric artery and this model shows it nice because it shows it running up up towards the stomach okay then these two branches right we have one going towards the spleen and one kind of going towards the duodenum all right the one going to the spleen namely is pretty easily right the splenic artery okay so this other branch right going towards the spleen would be the splenic artery then we have this guy all right this one is the common hepatic artery the common hepatic artery so we have the left gastric artery going up towards the stomach we have the splenic artery going towards the spleen which we see right here and then the common hepatic artery now it makes more sense when we talk about kind of one of these branches of that common hepatic artery so we see that common hepatic is going to bifurcate and go into two branches this one which is part of our portal triad which we'll get into in a second is called the hepatic proper artery or the proper hepatic artery okay so one of the branches off of that common hepatic artery would be the proper hepatic artery all right that proper hepatic artery is going to run up and supply blood to your liver okay so that's part of the portal triad so now it kind of makes more sense right why it's called hepatic or it has a padding in the name because eventually that proper hepatic artery is going to run up and supply blood to the liver okay and then the prefix for a lot of the structures relating to the liver is hepato okay like hepatitis inflammation of the liver right we have that proper hepatic artery okay supplying blood to the liver all right this other branch of the common uh hepatic artery is called the gastroduodenal artery and that's this guy right here okay gastroduodenal artery okay so we talked about this first branch which is a celiac trunk okay so that's the first branch of one yeah the first branch of the abdominal aorta okay so that's gonna be the celiac trunk okay now if we turn it around so now we can see all right this entire posterior view we can see a few of the same structures okay so we see the celiac trunk which again is the first branch off of that abdominal aorta all right the celiac trunk has three branches this one running up towards the stomach towards the lesser curvature of the stomach called the left gastric artery we have this guy running towards the spleen right which we know is the splenic artery and then this short little one which is called the common hepatic artery all right hepatic because one of the branches which is the proper hepatic artery runs up and is part of that portal triad all right so that's the first branch the celiac trunk off the abdominal aorta the second branch would be the superior mesenteric order all right so this is the superior mesenteric artery and it continues down all right and we can see it on the other side right so this would also be the superior mesenteric artery cool all right and those are all the arteries that we can see on the pancreas that we're concerned about okay so now let's go over the veins all right so let's turn this around all right because this is where we can see the majority of the veins right so now that we're on the posterior side all right we can see some of these veins a little bit clearer so as you can see from that anterior side we can only see one or two all right from the posterior we can see most of them all right so let me point this out first because this is kind of like the last collecting point for a lot of these veins okay so this is going to be the portal vein so this portal vein is part of what we know as the portal triad so i'm going to turn it up here right so this is again is the superior view these three vessels together make up what we know as the portal triad so this this group of vessels is going to go up towards the liver okay and we can name them all so we talked about this one which was the hepatic proper or the proper hepatic artery all right this blue guy which we now know is going to be called the portal vein okay the portal vein all right and then the green one of course would be the common bile duct okay these vessels are running up towards the liver and supplying blood to it and of course the bile duct is taking bile away from the liver okay all right so the reason i point that out first is because this is kind of like the last point where a lot of these vessels are draining into okay so let's talk about these other vessels okay first off we have this one which should be pretty easy right so this is the splenic vein okay so just like on the anterior side or i guess the superior side we can see that spunic artery right we also have that splenic vein okay we also have a splenic vein that splendid vein is going to continue and drain into what we know is the portal vein okay so we named this artery all right this is the superior mesenteric artery okay again we turn to this side we can see that this is also that superior mesenteric artery but next to it we have the um vein named the same right so the superior mesenteric vein so these two right the blue would of course be the superior mesenteric vein the red we already talked about would be the superior mesenteric artery okay so this guy the blue as well as this guy on the anterior side would be the superior mesenteric vein now likewise the superior mesenteric vein drains into the portal vein okay if that's the superior mesenteric vein this guy right here would then be the inferior mesenteric vein so the inferior mesenteric vein actually doesn't drain directly into the portal vein rather it drains into the splenic vein first and then into the portal vein okay so we see the splenic vein continuously running to right about here where it drains into the portal vein whereas the inferior mesenteric vein drains into the spinal vein first before it continues to drain into that portal vein all right and again that portal vein along with the rest of that portal triad is running up towards the liver okay so those are the arteries and the veins that we can see on this model