What is the normal size of the portal vein (PV)?

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Last updated: April 17, 2025View editorial policy

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From the Research

The normal portal vein diameter in adults is typically larger than the widely referenced upper limit of 13 mm, with a mean diameter of 15.5 mm as measured on CT scans. This measurement is based on a study of 191 healthy patients who underwent abdominal CT scans as potential renal donors, and the results showed that the mean main portal vein diameter was significantly larger than the commonly referenced upper limit of 13 mm 1. The study also found that portal vein diameter does not vary significantly when measured on axial vs. coronal images, but post-contrast main portal veins were 0.56 mm larger compared to non-contrast.

Some key points to consider when assessing portal vein diameter include:

  • Patient height and BMI are positively correlated with portal vein diameter 1
  • Sex, height, and BMI significantly affect main portal vein diameter 1
  • The normal portal vein diameter can vary slightly based on factors such as respiration, body position, and measurement technique
  • In children, the normal portal vein diameter is smaller and increases with age, generally correlating with body size and weight 2, 3, 4

It's worth noting that the normal portal vein diameter can vary depending on the population being studied and the measurement technique used. However, based on the most recent and highest quality study available, a mean portal vein diameter of 15.5 mm is considered normal in adults 1. This information is important for evaluating liver disease, as dilation of the portal vein can occur in conditions such as cirrhosis, portal vein thrombosis, or schistosomiasis.

Professional Medical Disclaimer

This information is intended for healthcare professionals. Any medical decision-making should rely on clinical judgment and independently verified information. The content provided herein does not replace professional discretion and should be considered supplementary to established clinical guidelines. Healthcare providers should verify all information against primary literature and current practice standards before application in patient care. Dr.Oracle assumes no liability for clinical decisions based on this content.

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