 Dr. Sanyal, Professor Department Chair, welcome to our section of the liver. In this specimen that you are seeing in front of us, we have completely removed not only the liver but also the entire foregut. But we shall not talk about the foregut. We have retained them just to show the anatomical continuity of the blood vessels. So let's focus only on the liver as it has been eviscerated out of the abdomen. So let's start with the surfaces. So this is the anterior superior surface of the netmaker right lobe and this is the posterior inferior surface. The anterior superior surface is also the diaphragmatic surface because that is in relation to the diaphragm and it's also the costal surface and it's related to the ribs. And we can see the costal markings here. The posterior inferior surface is also referred to as the visceral surface because it is related to all these viscera that are located here. Margin separating the two surfaces, this is the inferior margin of the liver. Normally this inferior margin of the liver is at the level of the costal margin on the right side. However, if the liver is enlarged, only then we can feel it in an adult. While in a child, the inferior margin may be one centimeter below the right costal margin but that is normal. The liver normally, because it is in contact with the right dome of the diaphragm, that is the reason why the right dome of the diaphragm is one space higher than the left dome. The liver normally has got a certain range of movement up and down with restoration. In the midline, it can move up and down about 4 to 8 centimeters and on the right midclavicular line it can move up and down about 6 to 12 centimeters. My assistant is holding up this ligament here. This is the phallus home ligament and this is attached to a fissure ear and that is what divides the liver into a right anatomical lobe and a left anatomical lobe. The right anatomical lobe is the one which is in relation to the right hypochondrium and the right dome of the diaphragm. The left anatomical lobe extends from the epigastrium and it extends a little bit into the left hypochondrium. Now let's take a look at the spaces around the liver. Imagine the diaphragm was located here at the right dome. So the space between the right dome of the diaphragm and the diaphragmatic surface of the liver, this is the sub-phrenic recess. This is the potential site of collection of infection. Then we have a space under the visceral surface of the liver. This is known as the sub-hypatic space and finally the posterior superior extension of the sub-hypatic space is where my finger is going in. Imagine the kidney was located here where my hand is located. This space will be the space between the liver and the kidney on the right side and that is known as the hepatorenal space or the Morrison pouch. The sub-phrenic space is divided into a right and a left half by the phallus home ligament and this communicates with the sub-hypatic space and the sub-hypatic space in turn, posterior superior extension of that is the Morrison pouch. This Morrison pouch is also communicating with the lesser sac which is in this region and their upper limit is limited by the posterior layer of the coronary ligament which I am going to mention just now. Incidentally, the Morrison's pouch, hepatorenal recess is one of the two most dependent portions of the peritoneal cavity when the patient is lying down. The other most dependent portion being the pelvis. So, these are some important anatomical spaces with surgical significance. Now, let us come to the ligaments which are visible on the liver. One we have already mentioned this is the phallus home ligament. The phallus home ligament is actually secret shape that is why it is called phallus home. It has got one margin which is attached to the liver and which is the one which divides the liver into the two anatomical lobes. The other margin is this one which was attached to the inner surface of the anterior abdominal wall and it has got a free margin which we can see here. This free margin has got some importance. The free margin of the phallus home ligament contains two structures. One of them is this round ligament of liver. This is the obliterated umbilical vein which in fetal life carried oxygenated and enriched blood from the placenta to the fetus. And this structure which is seen in adults, this is the parambilical vein. This parambilical vein goes through the free margin of the phallus home ligament and it goes and connects to the left branch of the portal vein which enters through the portahepatus. On the other side in the umbilicus, it has communications with the superficial epigastric vein. So, therefore, this forms an important site of portah systemic anastomosis. And this is the one which is responsible for getting in-laws and forming the capid medica in cirrhosis with portal hypertension. So, this is one ligament. Now, let's gently turn the liver and take a look at the diaphragmatic surface. The phallus home ligament splits into a right leaf and a left leaf. This forms the anterior boundary of the coronary ligament, this one. Then we have, if we turn the liver further, we see the cut margin of yet another ligament here. This is the posterior boundary of the coronary ligament. Within the posterior margin and the anterior margin, this portion of the liver that we can see, it is bare, it is completely bereft of peritoneum as compared to this surface and this surface. And this portion of the liver is referred to as the bare area of the liver because it is in direct convocation with the right dome of the diaphragm. And through here, the branches of the right phrenic nerve pass into and the branches of the lymphatics from the liver go through the bare area and they enter into the diaphragm and to the posterior medistinal lymph nodes. Where the anterior and the posterior leaves of the coronary ligament meet on the left side. Here they form a ligament which is referred to as the left triangular ligament. And likewise, where the anterior and the posterior leaves of the coronary ligament meet on the right side which has been cut here, here they form the right triangular ligament. And this coronary ligament and the triangular ligaments are one of the many structures which hold the liver in their place under the diaphragm. Now let's take a look at the fissures. So for that, we will again turn the liver. Now we are on the visceral surface or the so-called posterior inferior surface. We can see in front of us, this is the gallbladder. And the gallbladder has been separated from the bed of the liver and we can notice that there is a fissure here. This is referred to as the gallbladder fossa. And the gallbladder, as we know very well, it projects a little beyond the inferior margin of the liver. Now if we were to remove these structures aside and we will see yet a structure here where my instrument has gone in. This is the cut portion of the inferior vena keva. This is the lower portion of the inferior vena keva. This is the upper portion of the inferior vena keva. Here also we have a groove and this is called the fissure of the inferior vena keva. So if we were to consider the fossa of the gallbladder and the fissure for the inferior vena keva as one continuous limb separated only by the caudate lobe and the caudate process, this is referred to as the right sagittal fissure. The right sagittal fissure with an anterior limb and a posterior limb. The posterior limb being formed by the gallbladder fossa. The posterior limb being formed by the fissure for the inferior vena keva. In the very area of the liver, let's take a look at yet another fissure. We have gone a little to the left. We can see a fissure here. And this is the fissure for the round ligament of liver which I mentioned earlier and we can see this is the round ligament. And in continuity, we can see yet another fissure and this is the fissure for the ligamentum venosum. And if I pull it out, we can see the remnant of the ligamentum venosum. So, this again constitutes yet another complete and this whole thing is referred to as the left sagittal fissure. The anterior limb of the left sagittal fissure being formed by the fissure for the round ligament and the posterior limb of the left sagittal fissure being formed by the fissure for the ligamentum venosum. The ligamentum venosum incidentally is the remnant of the ductus venosus which in fetal life transmitted purified blood directly from the umbilical vein to the inferior vena cava and completely bypass the liver. Incidentally, in the fissure for the ligamentum venosum, we have the termination of this little bit of structure which has been retained here. This is the lesser momentum for the hepatogastric ligament. Now, to summarize quickly, we have now created one fissure here that is the right sagittal fissure with an anterior limb and a posterior limb and we have created the left sagittal fissure with an anterior limb and a posterior limb. And now, we will join these two limbs by means of one transverse limb here and that is known as the portahepatus where we have the three structures entering and leaving the liver namely the common bile duct, the branches of the hepatic artery and the portal vein. So, we have an edge shape formed by the right sagittal fissure, the left sagittal fissure and crossed over by the portahepatus. So, these are the anatomical fissures of the liver and this is going to be the basis for our next demonstration whereby we will convert these anatomical fissures into surgical fissures and the surgical segments and the hepatic veins. So, for that we will go to the next section. Thank you very much for being with us till this long. Stay tuned for the next video. If you have any questions or comments, please put them in the comment section below. Have a nice day. Dr. Sanjay Sanyal signing out.