16th February 2024

Other intra-abdominal organs

Liver

The liver is divided into four lobes: right, left, quadrate and caudate. Three major recesses around the liver serve as potential spaces for abscesses to develop around the liver, including the subphrenic recess, subhepatic recess and Morison’s pouch. 

All the major structures, except hepatic veins, enter and leave the liver at the porta hepatis. The portal vein, formed by the superior mesenteric and splenic veins, supplies about 75% of the blood to the liver. This contains deoxygenated, nutrient-rich blood from the GI tract and spleen. The remaining 25% of the blood is oxygenated and supplied by the hepatic artery. Hepatic veins drain the blood from the liver to the inferior vena cava.

Gallbladder

The liver secretes bile, which initially passes through the canaliculi, which join together to form intrahepatic bile ducts. The intrahepatic ducts will converge to form the right and left hepatic ducts. The right and left hepatic ducts combine to form a common hepatic duct. The common hepatic duct will converge with the cystic duct to form the common bile duct. 

The pancreatic duct will converge with the common bile duct at the ampulla of Vater before it drains into the duodenum. The gallbladder lies at the inferior surface of the liver and stores bile, which is excreted via the cystic duct. The gallbladder is divided into fundus, body and neck. The fundus of the gallbladder lies at the tip of the right ninth rib.

Pancreas

The pancreas is divided into head, neck, body and tail. The head lies in the cavity created by the C-shape of the duodenum. The pancreas extends across the midline and ends at the hilum of the spleen. The main pancreatic duct drains the exocrine part of the pancreas.

Spleen

The spleen is a part of the lymphoid system. It is connected through peritoneal ligaments to the stomach and left kidney. The splenic artery and splenic vein supply and drain the spleen, respectively.

Adrenal glands

Two adrenal glands lie adjacent to the superior pole of each kidney. These glands are supplied by the superior suprarenal artery, middle suprarenal artery, and inferior suprarenal artery, which are branches of the inferior phrenic, aorta and renal artery, respectively. The right adrenal is drained by a single vein directly into the IVC, while the left one drains into the renal vein.

References

Wineski, L. E., & Snell, R. S. (2019). Snell’s clinical anatomy by regions. 

Chaurasia, B. D. (2019). Human anatomy: Regional and applied, dissection and clinical. New Delhi, India: CBS Publishers & Distributors.

Moore, K. L., Dalley, A. F., & Agur, A. M. R. (2014). Moore’s Clinically Orientated Anatomy (7th ed.). China: Lippincott.