Calot triangle

Calot triangle or cystohepatic triangle is a small (potential) triangular space at the porta hepatis of surgical importance as it is dissected during cholecystectomy. Its contents, the cystic artery and cystic duct must be identified before ligation and division to avoid intra-operative injury.

Gross anatomy

Boundaries

The (isosceles) triangle is positioned so that the apex points towards the liver with the following boundaries:

• right: the cystic duct which is often tortuous and has a beaded appearance, passes downward and to the left to join the common duct
• left: common hepatic duct
• superior: the inferior surface of the liver (in the original description by Calot the superior boundary is the cystic artery)

Contents

• right hepatic artery
• cystic artery
• cystic lymph node (of Lund)
• connective tissue
• lymphatics
• occasionally accessory hepatic ducts and arteries

History and etymology

This space was first described by the French surgeon, Jean-François Calot (1861–1944)  in 1891, as part of his PhD thesis; although the triangle as described by Calot differs slightly from the modern description .