 Dr. Sanjay Sanyal, Professor, Department Chair. This is going to be a rather intricate dissection of the entire portahepatus, the structures of the extra-hepatic portal triad, the gallot strangle, and all the anatomical variations which pose a risk during cholestestectomy. This is the liver which we have completely removed and both of us are standing on the same side, the narration as well as the camera. This is the highly enlarged portahepatus and these three structures that you can see here, these are the structures of the extra-hepatic portal triad. This one is the common bile duct. This is the portal vein and this is the hepatic artery. In life, these three were highly closed and they were enclosed in the hepatic neural ligament which was attached to the margins of the portahepatus. We have completely separated them out. Let's take the structures one by one and see how they are related in the portahepatus. This structure which I have picked up here, this is the hepatic artery. We can see this is the stump of the common hepatic artery coming from the celiac trunk and this is the place where the common hepatic artery makes a curve and at the curve it is giving out this branch which is the gastrodural artery and after that it becomes known as the hepatic artery proper. This hepatic artery proper, it runs in the hepatic neural ligament and we can see it is dividing into these branches. We can see this branch here, this is the left branch of the hepatic artery and this branch, this is the right branch of the hepatic artery. Traditionally we know that the right branch of the hepatic artery goes behind the common hepatic duct. This is the common hepatic duct but in front of the portal vein and that is what it is doing. After that it goes into the liver and we also know that the right branch of the hepatic artery gives rise to the cystic artery. It is doing that. In the region of the callot strangle there are quite a few variations that we can experience in the hepatic artery. So what is this callot strangle? This is the callot strangle which again we have highly exaggerated. It is bounded by the cystic duct on one side, the common hepatic duct on the other side and the liver on the top. So this whole thing is the callot strangle which as I said has been highly exaggerated in this particular dissection. And what are the contents of the callot strangle? It is the cystic artery and cystic lymph nodes of Lund and this is the region that we dissect during colostectomy. So now let's come back to the variations that we can see in the hepatic artery. Normally the right branch of the hepatic artery as we mentioned it passes behind the common hepatic duct and in front of the portal vein. It is doing that. However in 25% of the cases the right branch of the hepatic artery goes in front of the common hepatic duct. Sometimes there can be an accessory or replaced left hepatic artery. Coming from the left gastric artery similarly sometimes there can be an accessory or replaced right hepatic artery which comes from the supramacentric artery. In 91% of cases the right hepatic artery goes in front of the portal vein. This is the portal vein. However in 9% of cases the right hepatic artery goes behind the portal vein. In this case it is following the normal feature. So these are some of the variations that we can see in the hepatic artery. Now let's take the common bile duct and the common hepatic duct. This is the common hepatic duct and we can see it is coming from the port of Hepatitis as the right and the left hepatic ducts. This junction we can have tumor which is known as clatskin tumor which is a special type of cholangiocarcinoma. Common hepatic duct then descends down and it unites with a cystic duct to form the common bile duct. So this is the callot strangle which we mentioned. Normally the cystic duct initially goes almost parallel to the common hepatic duct and then it becomes completely and then it unites to form the common bile duct which then continues down. This cystic duct can also have a lot of variations. It can have what is known as a very low cystic duct. In this case it is almost of that category. It is supposed to have united here instead it is uniting here. So this is a type of low cystic duct. Sometimes we can have a very high cystic duct when the cystic duct unites with the common hepatic duct here as I've shown. Then we can have the cystic duct following what is known as a swerving course. It goes like this behind or in front of the common hepatic duct like this and it unites with the common hepatic duct. Sometimes the cystic duct can have a separate hepatic duct uniting with it separately. Sometimes there can be multiple hepatic ducts coming from the portahepatus. All these variations pose a risk in cholecystectomy. When we are ligating the cystic duct we can accidentally ligate the common hepatic duct with it or we can even ligate the common bile duct with it and can produce a whole host of problems which are collectively known as post cholecystectomy syndrome. Now let's come to the next content of the short strangle that is the cystic artery. In this we can see that it is following a variation. Normally the cystic artery should arise from the right branch of the hepatic artery and we can see it is arising from the right branch. In 75% of cases it should be behind the common hepatic duct. Only in 25% of cases it comes in front of the common hepatic duct and in this case we are seeing it is coming in front of the common hepatic duct and then it enters into the gallbladder. Therefore when we are ligating this during cholecystectomy again we can ensure the common hepatic duct as we can see here. So again we can produce post cholecystectomy syndrome. If by chance we have bleeding from cystic artery during cholecystectomy and we cannot see because the whole area gets filled with blood we can do what is known as a Pringles maneuver where we put our index finger in the epiploid for MN as I've shown here and the thumb in front and we compress the hepatic artery and that's how we stop bleeding here and when we stop bleeding then we can catch the bleeding point and we can ligate it. That procedure can be a lifesaver both for the surgeon as well as for the patient and that is known as the Hogarth Pringle maneuver. So that is the next structure that we see here in the Colour Strangle and the Extrapatic Portal Triad. Now I'm going to lift this biliary system up and I've lifted up the hepatic artery to show the Pustiamo structure in the Extrapatic Portal Triad and that is this one here. This is the portal vein. The portal vein as we know is formed behind the neck of the pancreas by the union of slenic vein and the superior miscentric vein and the portal vein then goes into the port hepatus and this is the portal hepatus portal vein entry and we can see it is dividing into a left branch. This is the left branch of the portal vein and this is the right branch of the portal vein. The left branch of the portal vein goes into the left surgical lobe of the liver and we can see, this is the fissure for the round ligament of liver and the round ligament of liver is this one which was located in the free margin of the Falsiform ligament. Remnant of the Falsiform ligament is seen here And this round ligament of liver is connected to the left branch of the portal vein. And if you see very closely, we may be able to see some small veins accompanying the round ligament of liver. Those are the para-umbilical veins which open into the left branch of the portal vein. In cirrhosis with portal hypertension, these para-umbilical veins become enlarged and they go to the umbilicus and they form what is known as the caput medusa. So these are the structures that we can see in the port a hepatis. So therefore to quickly to recap, this is the common mild duct formed by the union of the cystic duct and the common hepatic duct. This is the hepatic artery giving rise to the left branch and the right branch. Right branch giving rise to the cystic artery. This is the portal vein dividing into a left and a right. And these are the structures of the extra hepatic portal triad. And this is the highly enlarged port a hepatis. Before concluding, this is the gallbladder which is in the gallbladder fossa. This is the fissure for the round ligament of liver. This portion of the liver that we see here is the quadrate lobe of the liver. And behind all these things we can see this is the inferior vena kiva. And this is the fissure for the ligamentum venosum. And we can see the remnant of hepatogastric ligament of the lesser momentum which is stuck here. So these are the structures which I wanted to show you in the port a hepatis, extra hepatic portal triad, gallot strangle with all the anatomical variations and the possible risks during cholecystectomy. Thank you very much for watching. Dr. Sanjay Sanyal signing out. Mr. Kendal Kambrabaj is a camera person. If you have any questions or comments, please put them in the comment section below. Have a nice day.