Often their gallbladders are removed, sometimes even if no stones are found, and the diagnosis is only made later when further investigations reveal the high pressure in the sphincter.
Another explanation for recurrent pain after a cholecystectomy is that more stones are present. Although stones usually form in the gallbladder, they can also form in the bile ducts, producing to the same symptoms. It may also be that a very tiny stone was left in the bile ducts at the time of surgery, and this stone has been slowly enlarging since. In rare cases, the duct leading into the gallbladder (the cystic duct) is not clamped and cut close to its base during the surgery. This can lead to an enlargement of the remaining part of the duct, which can also lead to more stone formation.”