MTBE was instilled in 6 cases of lithiasis (1 intrahepatic, 5 giant common bile duct stones following EPT). The nasobiliary route (3 cases) and a percutaneous biliary drain (3 cases) were used for this purpose. Complete stone dissolution was achieved in four cases. In the other two, volume reduction was sufficient to allow spontaneous elimination after EPT. A full clinical recovery was obtained in all cases. Further investigation is required in cases of intrahepatic and common bile duct stones when their removal by EPT is not enough to lead to clinical resolution. Follow-up is indispensable.