cbd ultrasound anatomy

A common anatomic variation is to have an extrahepatic junction of the right/left hepatic ducts.(20% of people)
It is useful to make note of this in the report, particularly if it is a very distal junction. During cholecystectomy surgery, the common duct is cannulated to image for duct calculi which may be missed. Also to avoid mistaking the RHD for the cystic duct.

Role of Ultrasound

Ultrasound image- A common variant is the common bile duct coursing below the hepatic artery. In colour (mouse over) it proves the hepatic artery (in blue) is anterior.

Extrahepatic Junction ultrasound image.

Even if the knowledge of the normal standard reference of the CBD diameter is crucial in the diagnosis and management of the biliary system pathology, there is not enough study for its standard measurement done in our population. There are many studies which try to assess the normal range of diameter of CBD, but many of the studies did not asses the normal value at different age and BMI groups [16]. Also most of studies done in this thematic area didn’t consider the methodological issue including sample selection and sample size calculation, so this study take under consideration of this issue.

Diseases and biliary disorders associated with biliary system obstruction affect a significant portion of the world’s population[7]. The size of the CBD is a predictor of this obstruction and an important component of biliary system evaluation. Prior knowledge on the internal measurements of the CBD diameter distinguished obstructive cause of jaundice from non-obstructive causes [5, 7] and the finding of abnormally dilated CBD is the most common indicators of choledochostomy. To evaluate the importance of CBD, it is necessary to know about the normal variations of CBD diameter[8, 9]. The assessment of common bile duct also helps for the evaluation of strictures or filling defects of hepatobiliary system [10].

See also  cbd and pain control

All relevant data are within the manuscript and its Supporting Information files.


Dependent variable; diameter of the common bile duct, independent variables; include Sociodemographic data age, sex, place of residence and anthropometric characteristics height, weight, and body mass index.

To measure the normal CBD diameter and its association with age, sex, and anthropometric measurement at the University of Gondar Comprehensive Specialized Hospital and selected private imaging center, Gondar town, Northwest Ethiopia, 2019.


There is no enough study for the standard measurement of CBD diameter among the Ethiopian population. So this study aims to assess the range of normal measurements of CBD diameter and its association with age, sex, and anthropometric measurement.

n = 200.9 = 201 subject, 2% non-response rate from other study [13], so 2/100× 201 = 4.02