Skip to content

Magnetic Resonance Angiography, Lower Extremity Venous System — With Intravenous Contrast

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

An MRA uses magnetic fields and intravenous contrast to image veins in the legs, helping evaluate narrowing, blockage, or blood clots.

Quick summary

["This imaging test helps determine whether blood flow through the veins in the legs is normal or obstructed."]

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

Key facts at a glance

LOINC
46324-0
Short code
MRA LE ves W contr IV
Synonyms
MRA LE ves W contr IV
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 angiography (MRA) is an imaging test that uses magnetic fields and injected contrast to show the blood vessels and blood flow in the lower-extremity venous system. It is not a standard blood test.

Why might I need this test?

Your clinician may order this test to investigate leg swelling, pain, or suspected deep-vein thrombosis. It may also be used to assess venous obstruction, chronic vein disease, or the location of veins before another procedure.

How is the test performed?

You will lie on a table inside an MRI scanner while images are taken. Intravenous contrast is usually given through a vein in your arm, and the scanner may also create images that show blood flow through the leg veins.

How do I prepare for the test?

Follow your imaging center's instructions and tell the staff about any prior contrast reaction, kidney disease, pregnancy, or implanted medical devices. The MRI scanner makes loud noises, so you may be offered ear protection or a call button.

Clinical interpretation

How abnormal results are interpreted and what conditions they suggest.

◆Associated findings1

Short name

Lower-extremity venous MRA with IV contrast

Frequently asked questions

Does this test use radiation?
No. MRI does not use ionizing radiation, although intravenous contrast is used to improve the appearance of the blood vessels.
Is intravenous contrast always required?
Contrast is commonly used for lower-extremity venous MRA, but the radiologist determines the appropriate protocol. Ask the imaging center if you have had a previous serious reaction to contrast.
Can this test confirm a blood clot?
MRA can help identify venous obstruction or deep-vein thrombosis, but the diagnosis and any treatment plan are based on the full imaging interpretation and your clinical evaluation.
  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