Common bile duct measurements in an elderly population.

We prospectively evaluated the diameter of the common bile duct in 1,018 patients between the ages of 60 to 96 over a 4 year period to determine if there is a significant change in its size with aging. All of the patients included in the study were being evaluated primarily for carotid or peripheral vascular disease. Any patients with a history of biliary disease (i.e., bilirubin level greater than 1.5 mg/ml, cholecystectomy, or cholelithiasis) were excluded. Ultrasonography of the common bile duct was performed only in those patients with no subjective abdominal pain or icterus. Our results demonstrated a small although statistically significant increase in the caliber of the common bile duct with increasing age (60 years old or less, mean diameter 3.6 mm +/- 0.2mm, versus over 85 years old, mean diameter 4 mm +/- 0.2 mm, P = 0.009). Although the common bile duct did increase in size with aging, 98% of all ducts remained below 6 to 7 mm, the commonly accepted upper range of normal.