Portacaval anastomosis
A portacaval anastomosis (also known as porto-systemic anastomosis or portal caval system) is a specific type of anastomosis that occurs between the veins of portal circulation and those of systemic circulation. The inferior end of the esophagus and the inferior part of the rectum are some of the most important sites of portal systemic anastomosis.
In portal hypertension, as in the case of cirrhosis of liver, the anastomoses become congested and form venous dilatations. Such dilatation can lead to esophageal varices and rectal hemorrhoids. Caput medusaes can also result.[1]
Specific types include:
Region | Name of clinical condition | Portal circulation | Systemic circulation |
Esophageal | Esophageal varices | Esophageal branch of left gastric vein | Esophageal branches of Azygos vein |
Rectal | Rectal Varices | Superior rectal vein | Middle rectal veins and inferior rectal veins |
Paraumbilical | Caput medusae | Paraumbilical veins | Superficial epigastric vein |
Retroperitoneal | Splenorenal Shunt[2] | Splenic vein | Renal vein, suprarenal vein, paravertebral vein, and gonadal vein |
(no clinical name)[3] | Right colic vein, middle colic vein, left colic vein | Retroperitoneal veins of Retzius | |
Intrahepatic | Hepatic pseudolesions[4] | Perihepatic veins of Sappey | Superior epigastric vein |
Patent ductus venosus | Left branch of portal vein | Inferior vena cava |
It can be one of the conditions caused by portal hypertension. A useful mnemonic is that portal hypertension causes problems in the butt, the gut, and caput. A dilated inferior mesenteric vein may or may not be related to portal hypertension. Other areas of anastomosis include:bare area of the liver as it connects to the diaphragm, the posterior portion of the gastrointestinal tract as it touches the posterior abdominal wall, as well as the posterior surface of pancreas. <p.362 Gray's Anatomy for Students Second edition>
References
- ↑ Gray's Anatomy for Students Gray H, Drake R, Vogl W, Mitchell A, Tibbitts R, Richardson P. Philadelphia: Elsevier/Churchill Livingstone; 2010. p. 226
- ↑ D'Souza, Donna. "Portal-systemic collateral pathways | Radiology Reference Article | Radiopaedia.org". radiopaedia.org. Retrieved 2016-08-12.
- ↑ "Surgicomania: Portal Hypertension". surgicomania.blogspot.co.uk. Retrieved 2016-08-12.
- ↑ Khader.O.Thabet, Mohammed Al. "Hepatic pseudolesion near falciform ligament | Radiology Reference Article | Radiopaedia.org". radiopaedia.org. Retrieved 2016-08-12.
- Compendio de Anatomía humana. Testut- LaTarjet
Clinically Oriented Anatomy. Keith Moore.
Gray's Anatomy for Students Second Edition, p. 362; Portacaval anastomosis