Splenic vein

The splenic vein runs along the posterior surface of the pancreas, carrying blood from the spleen to join the superior mesenteric vein and form the portal vein. On ultrasound, it is an important landmark for identifying the pancreas, as the body and tail of the pancreas lie anterior to the splenic vein. The splenic vein is evaluated for patency, diameter, and flow direction. Thrombosis of the splenic vein, which can occur as a complication of pancreatitis or pancreatic cancer, leads to isolated splenic vein hypertension and can cause gastric varices. In portal hypertension, the splenic vein may become dilated, and flow can become sluggish or even reversed. Assessment of the splenic vein is a standard component of a comprehensive abdominal Doppler examination.