Skip to content

Brain MRI Without Contrast

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

A brain MRI uses magnetic fields and radio waves to create detailed images without intravenous contrast, helping evaluate brain tissue, blood vessels, and fluid spaces.

Quick summary

["This imaging test evaluates the structure and function of the brain without injecting IV contrast dye."]

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

Key facts at a glance

LOINC
46333-1
Short code
MR Brst-Ul WO contr
Synonyms
MR Brst-Ul 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
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?

A brain MRI without contrast creates detailed pictures of the brain using magnetic fields and radio waves. It generally does not require gadolinium-based IV contrast dye.

Why might I need this test?

A clinician may order this test to investigate headaches, weakness, numbness, seizures, vision changes, head injury, or other neurologic symptoms. It can also help evaluate stroke, tumors, fluid buildup, and abnormalities of brain tissue.

How is the test performed?

You lie on a padded table that moves into the MRI scanner. The machine makes loud knocking or clicking sounds, and you may be asked to remain still or hold your breath briefly. The scan usually takes 20 to 60 minutes, depending on the images needed.

How do I prepare for the test?

MRI without contrast usually requires no fasting or special preparation. Remove metal items, secure loose hair, and tell the imaging center about implants, medication patches, pregnancy, or claustrophobia. Follow the facility's instructions because some safety restrictions apply.

Clinical interpretation

How abnormal results are interpreted and what conditions they suggest.

◆Associated findings1

Short name

Brain MRI without contrast

Frequently asked questions

Does this test use contrast dye?
No IV contrast dye is generally used for a brain MRI without contrast. If contrast imaging is needed, the care team will explain the purpose, risks, and preparation separately.
Is a brain MRI painful?
The scan itself is usually painless because no needles are needed for a non-contrast MRI. Some people feel anxious in the narrow scanner, but the technologist will explain options and can provide reassurance.
What if I have metal in my body?
Many medical implants and metal objects are MRI-compatible, but safety must be confirmed before the scan. Bring the implant information or identification card to the imaging center and tell the technologist about any metal devices.
  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