The portal vein is considered enlarged if it measures over what size?

The portal vein is considered enlarged if it measures over 13 mm in diameter. This threshold is significant as it helps in the evaluation of conditions like portal hypertension. An increase in the diameter of the portal vein can indicate increased pressure in the portal venous system, which may result from factors like liver cirrhosis, hepatic obstruction, or significant vascular diseases.

In clinical practice, a diameter exceeding 13 mm is a crucial indicator for sonographers and other medical professionals when assessing liver and vascular health. Monitoring the size of the portal vein is an essential aspect of abdominal ultrasound examinations, especially in patients with known liver disease or those presenting with related symptoms.