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Computed Tomography (CT) Scan Without Contrast

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

A CT scan that uses X-rays to create detailed images without injecting intravenous contrast material.

Quick summary

["This test uses X-ray imaging to evaluate organs, bones, blood vessels, and other structures without IV contrast."]

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

Key facts at a glance

LOINC
43525-5
Short code
CT WO contr
Synonyms
CT 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
ct
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 CT scan uses X-rays and a computer to create cross-sectional images of the body. The “without contrast” version does not use injected intravenous contrast material.

Why might I need this test?

Your clinician may order this test to evaluate unexplained symptoms, detect injuries or bleeding, look for infection, stones, blockage, or a mass, and assess the condition of organs and bones.

How is the test performed?

You will lie on a padded table while a CT scanner rotates around you and takes X-ray images. The scan is generally painless and usually takes only a few minutes, although the total visit may take longer.

How do I prepare for the test?

Follow the instructions provided by the imaging center, including any fasting or medication directions. Tell the care team if you might be pregnant, have recently received contrast, or have an allergy to contrast material.

Clinical interpretation

How abnormal results are interpreted and what conditions they suggest.

◆Associated findings1

Short name

CT Without Contrast

Frequently asked questions

Does a CT scan without contrast involve radiation?
Yes. CT scans use a small amount of ionizing radiation, but the dose is kept as low as reasonably achievable for the examination.
Is the scan painful?
The scan itself is usually painless. You may feel pressure from the table or hear loud clicking sounds, and you may be asked to briefly hold your breath.
Why might another CT scan with contrast be needed?
Contrast can make certain blood vessels, tissues, and abnormalities easier to see. If contrast is recommended, the imaging center will ask about kidney function and prior contrast reactions before administering it.
  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