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Magnetic Resonance Portal Venography, Without Contrast

Published: August 9, 2026Updated: August 16, 2026

An MRI examination of the portal veins, which carry blood from the digestive organs to the liver, performed without intravenous contrast.

Quick summary

["This MRI evaluates blood flow and blockages in the portal veins without using intravenous contrast."]

Medically reviewed by WellAlly Editorial TeamLast reviewed August 16, 2026Editorial policy

Key facts at a glance

LOINC
36543-7
Short code
MRA Portal v WO contr
Synonyms
MRA Portal v WO contr
Category
liver
Sample
serum
Container
Red-top tube (SST)
Units
N/A
Fasting
false
Population
adult
Sex
all
Age range
18–65 years
Method
mr-angio
Specimen volume
5 mL
Stability
Room temperature: 4h, Refrigerated: 24h, Frozen: 7d
Hemolysis max
500
Lipemia max
1000
Icterus max
500
TAT
4–24 hours
Order
routine

What is this test?

Magnetic resonance portal venography is an imaging test that produces detailed pictures of the portal venous system. It is used to evaluate the portal veins and the direction and pattern of blood flow toward the liver.

Why might I need this test?

Your clinician may order this test to investigate suspected portal vein narrowing or blockage, signs of portal hypertension, or changes in liver blood flow. It may also be used to monitor people with known liver or vascular conditions.

How is the test performed?

You lie on a table inside an MRI scanner, and several sequences of images are taken. The scan may include special blood-flow techniques, but no intravenous contrast is used.

How do I prepare for the test?

Follow the instructions from the imaging center. You may need to avoid eating or drinking for several hours, and you should tell the staff about implants, metal devices, pregnancy, or any difficulty lying still. Because no contrast is used, there is generally no need for a contrast-related wait period afterward.

Clinical interpretation

How abnormal results are interpreted and what conditions they suggest.

Abnormal findings may indicate a portal vein clot, narrowing, compression, or altered blood flow. These findings can be associated with portal hypertension, liver disease, or other vascular conditions, but the images must be interpreted together with the clinical examination and other tests.

Short name

Portal MR Venography

Frequently asked questions

Is this the same as a routine abdominal MRI?
No. This examination focuses specifically on the portal veins and may use specialized MRI sequences to evaluate blood flow.
Does the test use intravenous contrast?
No. This version of portal MR venography is performed without intravenous contrast.
Will I need to have blood drawn?
Usually not. A blood draw may be needed if the imaging center requires laboratory testing for MRI safety, but it is not part of the venography itself.
  1. 1
    MedlinePlus — Laboratory TestsSource
  2. 2
    Lab Tests OnlineSource
  3. 3
    Mayo Clinic — Tests & ProceduresSource

Click any link to access the full source. PubMed Central (PMC) links provide free full-text access.

This information is for educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment.

Medical Disclaimer

This content is for general informational and educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. Always seek the guidance of a qualified healthcare provider with any questions you have about a medical condition, and never disregard professional medical advice or delay seeking it because of something you read here.

If you think you may have a medical emergency, call your local emergency number or go to the nearest emergency department immediately.

Medically reviewed by WellAlly Editorial Team Last reviewed August 16, 2026. · Read our editorial policy