Anorectal varices
Encyclopedia
Anorectal varices refers to the dilation of collateral vessels due backflow in the veins of the rectum
. Collateral veins anastomose the inferior
and middle rectal veins
with the portal system
in the presence of portal hypertension
. Increased portal pressure causes increased pressure throughout the portal system and this causes backflow to occur, pushing blood into systemic veins at various anastomoses around the body. This can also most commonly occur in the oesophagus, causing oesophageal varices, and at the level of the umbilicus
, causing caput medusa.
Between 44% and 78% of patients with portal hypertension get anorectal varices.
(TIPS) has been shown to alleviate varices caused by portal hypertension. Successful treatment of portal hypertension that subsequently reduces anorectal varices provides a confirmation of the initial diagnosis, allowing for a distinction between varices and hemorrhoids, which would not have been alleviated by reduction of portal hypertension.
Rectum
The rectum is the final straight portion of the large intestine in some mammals, and the gut in others, terminating in the anus. The human rectum is about 12 cm long...
. Collateral veins anastomose the inferior
Inferior rectal veins
The lower part of the external hemorrhoidal plexus is drained by the inferior rectal veins into the internal pudendal vein....
and middle rectal veins
Middle rectal veins
The middle rectal veins take origin in the hemorrhoidal plexus and receive tributaries from the bladder, prostate, and seminal vesicle....
with the portal system
Portal venous system
In human anatomy, the hepatic portal system is the system of veins comprising the hepatic portal vein and its tributaries. It is also called the portal venous system, although it is not the only example of a portal venous system, and splanchnic veins, which is not synonymous with hepatic portal...
in the presence of portal hypertension
Portal hypertension
In medicine, portal hypertension is hypertension in the portal vein and its tributaries.It is often defined as a portal pressure gradient of 10 mmHg or greater.-Causes:Causes can be divided into prehepatic, intrahepatic, and posthepatic...
. Increased portal pressure causes increased pressure throughout the portal system and this causes backflow to occur, pushing blood into systemic veins at various anastomoses around the body. This can also most commonly occur in the oesophagus, causing oesophageal varices, and at the level of the umbilicus
Navel
The navel is a scar on the abdomen caused when the umbilical cord is removed from a newborn baby...
, causing caput medusa.
Between 44% and 78% of patients with portal hypertension get anorectal varices.
Diagnosis
Anorectal varices are often confused with hemorrhoids, as they have similar presentation. Hemorrhoids, however, are not associated with portal hypertension and are often caused by passing non-regular stool.Treatment
Typically, treatment consists of dressing the underlying portal hypertension. Some treatments include portosystemic shunting, ligation, and under-running suturing. Insertion of a transjugular intrahepatic portosystemic shuntTransjugular intrahepatic portosystemic shunt
A Transjugular Intrahepatic Portosystemic Shunt is an artificial channel within the liver that establishes communication between the inflow portal vein and the outflow hepatic vein...
(TIPS) has been shown to alleviate varices caused by portal hypertension. Successful treatment of portal hypertension that subsequently reduces anorectal varices provides a confirmation of the initial diagnosis, allowing for a distinction between varices and hemorrhoids, which would not have been alleviated by reduction of portal hypertension.