Table 1.

Classification of double gallbladder. Adopted from Mochizuki S, Makita T⁷

Type	Description of the anatomy
Type I	Diverticulum of the cystic duct
Type II	Diverticulum of the neck of the main gallbladder
Type III	A sac attached to the neck of the main gallbladder via a small cystic duct
Type IV	Connection of the accessory sac to the middle of the hepatic duct via a small cystic duct
Type V	Duplicated fundus of the gallbladder
Type VI	Accessory sac attached to a hepatic duct of lateral left lobe of the liver