Diameter of the common bile duct in the elderly patient: measurement by ultrasound

We wanted to assess the width of the common bile duct (CBD) in an asymptomatic elderly (> 75 years) population, since no previous report has particularly considered the important age-related increase in CBD diameter for this patient group. CBD width of 92 asymptomatic people over 75 years of age (mean 84.7 years, range 75–96 years) without clinical or laboratory evidence for biliary, hepatocellular or pancreatic disease was measured by real-time high-resolution ultrasound of the upper abdomen. All examinations were performed by one experienced radiologist. Mean values were calculated for three groups: patients with and without cholecystolithiasis and after cholecystectomy. Statistical analysis was carried out by analysis of variance. Considering the measurements of all patients, the mean width (± SD) of the CBD was calculated as 6.5 ± 2.5 mm. The difference between patients without cholecystolithiasis (6.2 ± 2.3 mm) and patients after cholecystectomy (8.7 ± 2.9 mm) was statistically significant (P < 0.0001). Cholecystolithiasis (6.0 ± 1.6 mm) proves not to be an additional factor for CBD widening in comparison with patients without stone disease. The CBD of these very elderly subjects shows a considerable increase in comparison with the recommended borderline values in the ultrasound literature. An upper limit of 10 mm seems reasonable for patients with and without cholecystolithiasis. A significant increase in CBD width after cholecystectomy was found and measurements up to 14 mm may occur. Measurements have to be correlated with clinical and laboratory findings. Received 1 December 1997; Revision received 27 February 1998; Accepted 3 March 1998