Journal Home Page www.bbbulletin.org BRITISH BIOMEDICAL BULLETIN Original Clinicoanatomical Study of Blood Supply of Extrahepatic Biliary Ductal System Sachin Patil*1, Kumkum Rana 2, Smita Kakar 3 and A K Mittal 4 1Senior Resident, Dept of Anatomy, MAMC 2Professor, Dept of Anatomy, North DMC Medical College 3DirectorProfessor,Dept of Anatomy,MAMC 4HOD, Dept of Forensic medicine, VMMC & Safdarjung Hospital. New Delhi A R T I C L E I N F O A B S T R A C T Received 14 June 2014 Received in revised form 22 June 2014 Accepted 27 June 2014 The major blood supply of extrahepatic biliary ductal system is by cystic artery, which supplies to cystic duct, common hepatic duct and the upper part of the common bile duct. The lower part of bile Keywords : Cystic artery, duct is supplied by gastroduodenal artery. The present study is Extra hepatic, aimed at determining the anatomical variations of blood supply of Bile ducts, extrahepatic biliary ductal system and its clinical implications. The Variations, Laparoscopic cholecystectomy. present study of the blood supply of extrahepatic biliary ductal system has been conducted on 30 cadavers. After exposing the abdominal cavity and removing peritoneal fat, extrahepatic biliary system and its blood supply was carefully dissected and relevant photographs were taken. Special attention was given to the relationship of the cystic artery to the Calot’s triangle. Along with the arteries, the variations in the venous drainage were also noted. Major importance of knowledge of blood supply of extrahepatic biliary ductal system may well lie in the understanding of the etiology of postoperative bile duct strictures and in their prevention. A clear understanding of the major arterial supply to Corresponding author: Department of Anatomy Maulana Azad Medical College, the extrahepatic bile ducts should be of assistance in biliary Bahadhur shah zafar marg, New Delhi- reconstruction and treating hemobilia. 110002,India E-mail address: [email protected] © 2014 British Biomedical Bulletin. All rights reserved Introduction The cystic artery is the chief source pancreaticoduodenal artery. The right and of blood supply to gallbladder, cystic duct, left hepatic ducts are supplied by the right common hepatic duct and the upper part of and left hepatic arteries and their sectoral or the bile duct. The lower part of bile duct is segmental branches. 1,2 supplied by ascending marginal vessels Knowledge of relevant anatomy is derived from the postero-superior important for the safe execution of any Patil et al______________________________________________________ ISSN-2347-5447 operative procedure. Specifically, in the dissection for academic purpose, before the context of a cholecystectomy, it has been disturbance of liver and extrahepatic biliary recognized since long that misinterpretation ductal system by students. Abdominal cavity of normal anatomy as well as the presence was exposed by making a midline incision of anatomical variations contribute to the from xiphoid process to the pubic symphysis occurrence of major postoperative and carrying this incision to the right complications especially biliary injuries. anterior superior iliac spine. After exposing There is now a fair amount of data to the abdominal cavity and removing suggest that the acceptance of laparoscopic peritoneal fat, extrahepatic biliary system cholecystectomy as the standard procedure was carefully dissected and relevant has led to an increase in bile duct injuries. photographs were taken. Special attention This seems partly related to the different was given to the relationship of the cystic anatomical exposure of the area around the artery to the Calot’s triangle. Along with gallbladder especially the Calot's triangle the arteries, the variations in the venous during the laparoscopic procedure as drainage were also noted.In post-mortem opposed to the open procedure. 3 cases, all the observations were taken before The Calot’s triangle is an anatomical removal of abdominal viscera for post space bounded superiorly by the inferior mortem examination. These observations border of the liver, inferiorly by the cystic were taken in similar manner to those taken duct and medially by the right hepatic duct. in cadavers. The most common variant of Calot’s triangle, which is bounded medially by the Observation and Results common hepatic duct, was adopted, and currently the name ‘hepatobiliary triangle’ is The cystic artery was the chief source suggested. 4 of blood supply to cystic duct, common Major importance of knowledge of hepatic duct and the upper part of the blood supply of extrahepatic biliary system common bile duct .The lower part of common may well lie in the understanding of the bile duct was supplied by the branches of etiology of postoperative bile duct strictures gastroduodenal artery and posterosuperior and in their prevention. 5 pancreaticoduodenal artery. Our study showed that in all the cases the right and left Materials and Methods hepatic ducts were in the substance of liver. Hence their blood supply was not included in The present study of the blood the study. The origins of the cystic artery supply of extrahepatic biliary ductal system were from the right hepatic artery in half of has been conducted on 30 cases: Cadavers the cases (50%) which was very low as (15) in the Departments of Anatomy, compared to other studies. In other cases Maulana Azad Medical College and Bodies (50%), the cystic arteries arose from the (15) undergoing post-mortem in the hepatic artery proper(40%), the common Department of Forensic Medicine and hepatic artery(3.3%), the celiac trunk(3.3%), Toxicology, Maulana Azad Medical or the gastroduodenal artery(3.3%) (Figure1- College, New Delhi. Before the 2). commencement of study, the research In 86.6 % (26 out of 30) of all the proposal was reviewed and approved by a cases studied, the cystic artery coursed human research ethics committee of college. through the Calot’s triangle to reach the In cadavers, all the observations were taken gallbladder. Only in 13.3% (4 out of 30) of when the abdomen was opened for the cases did the cystic artery not pass BBB[2][2][2014]447-459 Patil et al______________________________________________________ ISSN-2347-5447 through the triangle. In our study 36.6 % (11 superior pancreaticoduodenal (0.3%), right out of 30) of all the cystic arteries ran gastric (0.1 %), celiac trunk (0.3 %) and posterior to the common hepatic duct as they superior mesenteric artery (0.8%). 6,7 entered the Calot’s triangle.40 % (12 out of The cystic artery may arise from any 30) of the cystic arteries ran anterior to the of the above-mentioned arteries, but it usually common hepatic duct.23.3 %( 7 out of 30) of arises from the right hepatic artery, which is cystic arteries were not related to common one of the terminal branches of the proper hepatic duct. Our study have shown that the hepatic artery. The cystic artery from the right cystic artery was a single vessel in as much as hepatic artery is usually given off in the 93.3%(28 out of 30 cases).Our study showed Calot's triangle. It has a variable length and double cystic artery in 6.6% (2 out of enters the gallbladder in the neck or body 30) (Figure 3). area. The course and length of the cystic The gastroduodenal artery was a artery in the Calot's triangle is variable. source of the cystic artery in 3.3% (1 out of Although classically the artery traverses the 30) cases. The origin of the cystic artery from triangle almost through its center, it can the trunk of the proper hepatic artery, was occasionally be very close or even lower than observed in this research in 40 %(12 out of the cystic duct. The cystic artery passes 30) cases, which is very high as compared to behind the common hepatic duct (CHD) to other studies. The common hepatic artery was the superior aspect of the gallbladder's neck, a source of the cystic artery in 3.3% (1 out of where it descends to the body of gallbladder. 30) cases. The celiac trunk was a source of It bifurcates into a superficial branch, running the cystic artery in 3.3% (1 out of 30) cases. along the peritoneal surface (subserously) of Derivation of the cystic artery from the left the gallbladder, and a deep branch, which hepatic artery was not seen in any of our runs between the gallbladder and the cases. In most of the cases two cystic veins gallbladder fossa. The two arteries were draining the venous blood from the gall anastomose and yield small branches that bladder (93.3%).These cystic veins entered enter the gallbladder parenchyma. 3,6,8, the liver in most of the cases (89.2%). In During development, the extra-hepatic some cases the veins drained into the portal biliary system arises from an intestinal vein outside the liver (10.7%).The common diverticulum, which carries a rich supply of hepatic duct, cystic duct and common bile vessels from the aorta, coeliac trunk and duct drained directly into portal vein through superior mesenteric artery. Later most of small veins in all the cases. The venous these vessels are absorbed, leaving in place drainage of RHD and LHD cannot be studied the mature vascular system. As the pattern of because the ducts were present in the absorption is highly variable, it is not unusual substance of liver and common hepatic duct for the cystic artery and its branches to derive was form within the liver. (Figure 4) from any other artery in the vicinity (Nowak, 1977). 7 Discussion In our study the origins of the cystic artery were from the right hepatic artery in Arteries distributed to the extrahepatic half of the cases (50%). In other cases (50%), biliary system show great variability in size these arose from the hepatic artery proper, the and it is difficult to treat hemorrhages during common hepatic artery, the celiac trunk, or or after biliary operations.