<prompt> Which of the following does not form the boundary of calots triangle -Cystic ductCommon hepatic ductCytic arteryVisceral surface of spleen  <response>: Ans. is d i.e., Visceral surface of Spleen Calots Triangle: Calots triangle or the hepatobiliary triangle is the space bordered by the cystic duct inferiorly, the common hepatic duct medially and the superior border by cystic artery. This was described in 1891 by Jean-Frantois Calot. It is an important surgical landmark and should be identified by surgeons performing a cholecystectomy to avoid damage to the extrahepatic biliary system.Note: In the original description by Calot the cystic artery is defined as the superior margin. But now most textbooks mention inferior surface border of right lobe of liver as the superior margin. 