From the Research
The normal main portal vein size in adults typically ranges from 9 to 15.5 millimeters in diameter when measured by CT, with a mean diameter of 15.5 mm as reported in the most recent study 1. This measurement is crucial for diagnosing and monitoring portal hypertension and related conditions. Several factors can influence portal vein size, including:
- Body position
- Respiratory phase
- Meal status, with measurements typically larger after eating
- Age and body size, with children having smaller diameters and larger individuals potentially having slightly wider normal ranges Portal vein enlargement is clinically significant as it may indicate liver disease, cirrhosis, or other conditions causing increased portal pressure. Conversely, a small portal vein may suggest thrombosis or hypoperfusion. According to the study by 1, patient height and BMI are positively correlated with main portal vein diameter, and contrast-enhanced main portal veins are significantly larger than unenhanced. It is essential to consider these factors when measuring portal vein size to ensure accurate diagnosis and monitoring of portal hypertension and related conditions. The most recent study 2 provides a comprehensive review of the portal vein, including its anatomy, variants, and disorders, which can aid in the diagnosis and treatment of portal vein-related conditions. However, the study by 1 provides the most recent and highest quality evidence for the normal main portal vein size in adults.