American Board of Surgery Qualifying Exam (ABS QE) Practice Test 2025 - Free Surgery Exam Practice Questions and Study Guide

A choledochal cyst is a congenital dilation of the biliary tree, and they are classified based on the American Association for the Study of Liver Diseases (AASLD) classification system. The types range from Type 1 to Type 5, each describing different characteristics of the cystic dilation.

In this context, Type 3 choledochal cysts are characterized as intraduodenal, meaning the cyst is located within the duodenum and often appears as a low cyst in the common bile duct (CBD). This type can commonly lead to complications such as biliary obstruction or pancreatitis due to its proximity to both the bile duct and the duodenum.

Type 1, the most common type, refers to fusiform dilation of the CBD, which is not considered a “low CBD cyst.” Type 2 involves an extrahepatic cyst that is typically a diverticulum off the CBD. Type 4 describes multiple cysts, which involve both intrahepatic and extrahepatic bile ducts and certainly do not align with the specific anatomical feature of a low CBD cyst.

Thus, the identification of a low cyst in the CBD correlates specifically with the characteristics defined in Type 3 choledochal cysts, making