Supplementary Material for: Calculus cholecystitis complicated with variations of extra-hepatic bile duct: Clinical experience and aeromedical analysis of 3 cases in aviation pilots

For aviation personnel, calculous cholecystitis often requires surgical treatment because of the potential risks to flight safety whether symptomatic or asymptomatic. Although much effort has been put on the precaution of gallstone formation, the incidence of long-term post cholecystectomy syndrome (PCS) seems more apparent in the limited number of cases undergoing cholecystectomy. The purpose of article is to elucidate the possible mechanism of gallstone formation and the development of long-term PCS caused by variations of bile duct, as well as choice of surgical treatments, just in this particular group of aviation personnel. Seven aviation pilots who underwent laparoscopic cholecystectomy in recent 5 years were reviewed, and 3 cases who developed long-term PCS because of variations of bile duct were presented. Variations of bile duct included existence of accessory extrahepatic bile, absence of common bile duct, and absence of cystic duct. Long-term PCS was characterized as epigastric dull pain and diarrhea or sparse stool, and became aggravated when resuming trainings of flight stimulations. Dietary adjustment and oral antispasmodic or cholagogic drug therapy, combined with relieving apprehensions after surgery, helped them recover well and resume flight. In conclusion, variation of bile duct maybe an important potential risk for gallstone formation and development of long-term PCS with the cause of probable decrement of bile drainage under the physiological environment of aviation.