Biomedical
Variations in extra-hepatic biliary tree morphology and morphometry: a narrative review of literature with focus on cystohepatic triangle
Artur Pasternak
Artur Pasternak
Department of Anatomy, Jagiellonian University, ul. Kopernika 12, 31-034 Kraków, Poland
Abstract
The morphometry and morphology of the components of extrahepatic biliary tree show extensive variations. A beforehand recognition of these variations is very crucial to prevent unintended complications while performing surgeries in this region. This study was conducted to analyze the configuration of the extrahepatic biliary tree and its possible variations, as well as measure the components that limit the cystohepatic triangle. Articles were searched in major online indexed databases (Medline and PubMed, Scopus, Embase, CINAHL Plus, Web of Science and Google Scholar) using relevant key words. A total of 73 articles matched the search criteria of which 55 articles were identified for data extraction. The length of left and right hepatic duct in majority of studies was found to be >10 mm. A wide range of diameters of hepatic ducts were observed between 5-43 mm. The average length of cystic duct is around 20 mm. The length and diameter of the common bile duct are 50-150 mm and 3-9 mm respectively. The most frequently observed pattern of insertion of cystic duct into common hepatic duct is right lateral, rarely anterior, or posterior spiral insertion can present. The results of this study will provide a standard reference range which instead will help to differentiate the normal and pathological conditions.
Key Questions
What is the extrahepatic biliary tree, and why is it important?
The extrahepatic biliary tree is a network of ducts outside the liver that carry bile to the gallbladder and small intestine. It includes the hepatic ducts, cystic duct, and common bile duct. Understanding its structure is crucial for surgeries in this area, as variations in anatomy can lead to complications if not recognized beforehand.
What was the goal of this study?
The study aimed to analyze the anatomy and variations of the extrahepatic biliary tree, as well as measure the structures that define the cystohepatic triangle (an important surgical area). By doing this, researchers hoped to create a reference guide to help surgeons distinguish between normal and abnormal anatomy.
How was the study conducted?
Researchers reviewed 73 articles from major medical databases like PubMed and Scopus, focusing on studies that described the anatomy of the extrahepatic biliary tree. They extracted data from 55 articles that met their criteria, analyzing measurements and variations in the ducts.
What were the key findings?
The study found that the left and right hepatic ducts are usually longer than 10 mm, with diameters ranging from 5 to 43 mm. The cystic duct is about 20 mm long on average, while the common bile duct is 50–150 mm long and 3–9 mm wide. The most common way the cystic duct connects to the common hepatic duct is from the right side, but it can also spiral around the front or back in rare cases.
Why are these findings important for surgeons?
Knowing the normal size and shape of these ducts, as well as their possible variations, helps surgeons avoid mistakes during procedures like gallbladder removal or bile duct surgery. This study provides a standard reference range to help identify when something is abnormal, reducing the risk of complications.
What is the cystohepatic triangle, and why does it matter?
The cystohepatic triangle is a critical area in surgery, defined by the cystic duct, common hepatic duct, and the liver. It’s where surgeons often work during gallbladder procedures. Understanding the anatomy of this area is essential to avoid damaging nearby structures like blood vessels or bile ducts.
