The hepatoduodenal ligament is a portion of the lesser omentum that lines the abdomen. It is a peritoneal ligament in the abdomen that connects to the duodenum of the intestines. This ligament begins as a double layer of serous membranes that form part of the peritoneum, which is the lining of the abdominal cavity that begins at the liver. The portal triad of the liver is contained within the hepatoduodenal ligament.
Enclosed within a fibrous capsule between the two layers of the serous membrane are five separate anatomical structures. The encapsulated sheath is called the Glisson’s capsule of the liver. Three of the structures make up the hepatic portal triad. They are the hepatic portal vein, the hepatic artery proper, and the common bile duct.
The lesser omentum, or gastrohepatic omentum, transitions into the hepatoduodenal ligament at the transverse fissure of the liver, which is also called the porta hepatis. It is located on the left side of the right lobe of the liver. The hepatic portal vein and the hepatic artery proper enter the liver at the porta hepatis, and the common hepatic duct leaves the liver at the porta hepatis into the hepatoduodenal ligament.
Inside the ligament, the hepatic portal vein collects blood from the spleen and the gastrointestinal tract. The accumulated blood is eventually deposited into capillary beds found within the liver. Next to the hepatic portal vein is the hepatic artery proper, which helps supply blood to the liver. Once the common hepatic duct exits the porta hepatis of the liver, it combines with the cystic duct of the gallbladder, and becomes the common bile duct.
Additional anatomical structures are present within the hepatoduodenal ligament. A branch of the vagus nerve runs throughout the ligament next to the portal triad. Lymph vessels, which absorb interstitial fluid, bacteria, and leaked blood cells, also travel through this ligament before draining the collected lymph into a lymph duct.
Disorders involving the hepatoduodenal ligament are varied. Some cancers may spread, or metastasize, through this ligament. It can become infected, and form a painful pocket of infection called an abscess. The abscess may need to be visualized through a computerized tomography (CT) scan. These images enable the surgeon to determine if the surgical removal of the mass is necessary, and can be used as a guide for the surgeon during the operation.
During surgical procedures involving the abdomen, it is common for a surgeon to clamp the hepatoduodenal ligament with an instrument called a hemostat. The hepatic artery proper and the hepatic portal vein are compressed within the ligament, cutting off the flow of blood from the liver. This surgical technique reduces the amount of blood lost during open abdominal surgeries.