This large vein receives blood from several other veins (tributaries) in the digestive tract.
It lies to the right of the superior mesenteric artery.
Once in the liver, the nutrients can be dispersed throughout the body.
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The SMV joins with the splenic vein and becomes the hepatic portal vein.
Still other contributing veins come from the stomach and thepancreas.
In some people, the SMV may have one main trunk.
In others, it may be split into two.
A midgut malrotation is a congenital condition (one that a person is born with).
It often does not cause any symptoms, and its unknown how often it occurs.
Being diagnosed as an adult is rare.
Surgery might be done to correct any complications such as a bowel obstruction or a twisted bowel.
There are some differences in how the tributary veins connect to the SMV.
These variations can be diverse and complex.
ACT angiographyscan or another test may be done to look for these differences.
Understanding any variations may help in avoiding certain surgical complications.
Function
The purpose of the SMV is to transport blood from the digestive tract to the liver.
The blood comes from the small intestine, large intestine,appendix,stomach, and pancreas.
Blood coming from the midgut contains vitamins and nutrients from the food that is digested there.
In the liver, the nutrients are processed into a form that the body can use.
The liver stores these nutrients and parses them out when the body has a need.
Clinical Significance
Some conditions can affect the SMV.
In most cases, they are uncommon or rare.
Before the era of antibiotics, the condition was uniformly lethal.
Symptoms can include fever, abdominal pain, liver dysfunction, and a bacterial infection in the blood.
Pylephlebitis is often treated with antibiotics.
It is a rare condition.
This condition is most often diagnosed with aCT scan.
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