Esophageal varices are enlarged veins in the esophagus. They're often due to obstructed blood flow through the portal vein, which carries blood from the intestine, pancreas and spleen to the liver. Scarring (cirrhosis) of the liver is the most common cause of esophageal varices. This scarring cuts down on blood flowing through the liver. As a result, more blood flows through the veins of the esophagus. The extra blood flow causes the veins in the esophagus to balloon outward. Both abdominal CT scans and Doppler ultrasounds of the splenic and portal veins can suggest the presence of esophageal varices.