Caliber of the common bile duct: effect of cholecystectomy and other factors in a ultrasonographic study of 8534 patients.

OBJECTIVE

The objective of the present study was to analyze the effects of different factors impacting the caliber of the common bile duct (CBD) and a comparison of maximum extrahepatic bile duct caliber in patients with and without a history of cholecystectomy.

MATERIAL AND

METHODS

A retrospective data analysis was undertaken of 8534 patients (4480 females; 4054 males; average age: 59.2±18.0 years) with sonographic documentation of bile duct caliber. Maximum intra- and extrahepatic bile duct diameters were studied. The normal maximum diameter of the extrahepatic bile duct was defined as 7 mm. In patients who had undergone prior cholecystectomy, a maximum bile duct diameter<10 mm was considered normal.

RESULTS

The average maximum diameter of the CBD amounted to 5.3±3.0 mm for the overall collective. In patients who had undergone prior cholecystectomy, maximum CBD diameters in the normal range (<7 mm) were documented in 55%, while larger diameters (>7 mm) were observed in 45%. In the collective of patients without prior cholecystectomy, CBD diameters in the normal range (<7 mm) were found in 81%, with larger diameters observed in only 18.4% of patients. In both subgroups, there was a significant association between age and bile duct diameter (for those with prior cholecystectomy, p=0.0003; without prior cholecystectomy, p<0.0001). No statistically significant influence on CBD diameter was observed for either prior cholecystectomy (p=0.2116) or time interval since cholecystectomy (p=0.3537). Females, both with and without a history of prior cholecystectomy, showed a 1.4-1.5-fold higher risk of exhibiting a CBD diameter>7 mm (for those with prior cholecystectomy, p=0.0485; without prior cholecystectomy, p<0.001).

CONCLUSIONS

Our data show a positive correlation between age and CBD diameter. There was no statistically significant relationship between CBD diameter and prior cholecystectomy, postoperative interval and BMI.