Duplicated gallbladder

Duplication of the gallbladder is a rare congenital anomaly and thought to be due to an exuberant budding of the developing biliary tree with formation of two or more rudimentary gallbladders or due to failure of normal recanalisation of the gallbladder following solid stage of development [1]. Edward Boyden (1926) identified several types of duplicated gallbladder such as bilobed or bifid gallbladder which is considered as an incomplete variety and it is due to division of gallbladder by a septum or a diverticulum arising from part of the gallbladder [2,3]. Complete or the true duplication of gallbladder that does not communicate with each other and has two separate cystic ducts. The two cystic ducts can enter the common bile duct separately and form a H shape configuration (ductular type), or the Y shape where the two ducts unites to form a common origin. In ductular type one duct may open into intrahepatic ducts and part of the duplication can be intrahepatic [2,3]. Most of the duplicated gallbladder gives a clinical picture similar to other gall bladder diseases such as biliary colic, cholecystitis, obstructive jaundice and pancreatitis [4]. Complications of double gall bladder include torsion, papilloma, carcinoma, common duct obstruction and biliary cirrhosis. Grey scale ultrasound scan depicts two separate gallbladders as two separate cystic structures although demonstration of ductal anatomy or the type of duplication is not possible. Several conditions can mimic duplication of gallbladder, such as a folded gallbladder, bilobed gallbladder, choledochal cyst, pericholecystic fluid, gallbladder diverticulum, vascular band across the gallbladder and focal Adenomyomatosis [5]. Oral Cholecystogram demonstrate filling of contrast into two separate gallbladders and two separate cystic ducts. Opacification of two ducts can be enhanced by contraction of gallbladder after a fatty meal. Confusion occurs in cases where one gallbladder is involved with pathology where the normal gallbladder would be demonstrated and the abnormal gallbladder would not be outlined with contrast [2, 3]. Ductal anatomy is better defined by Endoscopic retrograde cholagiopanceatography ( ERCP), CT cholangiography and contrast enhanced MRCP (MR cholangiopancreatography) with mangafodipir trisodium. ERPC is considered the gold standard study in defining ductal anatomy. CT cholangiography had shown to be more useful in demonstrating ductal anatomy due to its higher spatial resolution compared to MRCP [5].