We aimed to determine the mean biliary confluence angle on MR cholangiopancreatography (MRCP) images and investigated the variability of the angle by age, gender, and body mass index.

Material and Methods:

The study population was drawn from the patients referred to MRCP between May 2006 and December 2006 for various indications; the most being for abnormal liver function tests or suspected biliary disease. A total of 40 patients (18 women and 22 men, age range 22-86 years) who denied a history of prior liver surgery, and in whom MRCP excluded bile duct variations, biliary diseases or chronic parenchymal liver disease were enrolled. The confluence angle was measured independently by 2 observers on 3 successive coronal oblique thick-collimation images where the angle is widest and the mean values were noted for each observer.

Results:

Statistically there was almost perfect agreement between 2 observers (p<0.001, intraclass correlation coeffıcient= 0.93). The mean value was 87.87± 22.92 degrees for the lst observer (range 51-155 degrees) and 85.40± 25.80 degrees for the 2nd observer (range 45-166 degrees). No statistically significant correlation was found between biliary confluence angle and age, gender or body mass index. The lower and upper bounds of 95% confîdence interval for mean were 80.54-95.20 degrees for the lst observer and 77.14-93.65 degrees for the 2nd observer.

Conclusion:

Normal biliary confluence angle is independent of age, gender, and body mass index.

Keywords: Biliary Tract, Cholangiopancreatography, Bile Ducts