Portal Vein Diameter on Routine Clinical CT: Establishing Normals and Disease Associations

Area of Science:

• Radiology and Imaging
• Hepatology
• Vascular Medicine

Background:

• Portal hypertension is a severe complication of chronic liver disease, contributing to significant morbidity and mortality.
• Portal vein diameter on imaging is a proposed non-invasive marker for portal hypertension, but reference values and population associations require further characterization.

Purpose of the Study:

• To establish contemporary reference values for portal vein diameter using computed tomography (CT).
• To investigate associations between portal vein diameter and demographic, clinical, and imaging factors.
• To evaluate the diagnostic performance of portal vein diameter for identifying portal hypertension.

Main Methods:

• Retrospective analysis of 20,225 CT scans.
• Automated segmentation of the main portal vein and extraction of maximum diameter.
• Statistical analysis including linear mixed-effects models, logistic regression, and Cox regression to assess associations with various factors and outcomes.

Main Results:

• The mean portal vein diameter was 12.4 mm, influenced by sex, BMI, height, age, and CT contrast use.
• A 1-mm increase in portal vein diameter correlated with higher odds of prevalent liver disease (OR 1.06) and portal hypertension (OR 1.18).
• In liver disease patients, larger portal vein diameter predicted an increased risk of esophageal varices and ascites.

Conclusions:

• Mean portal vein diameter on routine CT is 12.4 mm and varies with demographic and imaging characteristics.
• Increased portal vein diameter is associated with liver disease, portal hypertension, and adverse outcomes like varices and ascites.
• Portal vein diameter serves as a practical tool for screening or enrichment in multimodal clinical approaches for portal hypertension.