CT Angiography With and Without Intravenous Contrast
This CT imaging study uses contrast-enhanced and noncontrast images to examine blood vessels, blood flow, and possible narrowing, blockage, or other vascular abnormalities.
["A CT angiogram with and without contrast helps evaluate the condition and blood flow of blood vessels."]
Key facts at a glance
- LOINC
- 87860-3
- Short code
- CT TA WO contr
- Synonyms
- CT TA 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?
CT angiography, or CTA, is an imaging test that uses computed tomography and often iodinated intravenous contrast to create detailed pictures of blood vessels. This version includes both contrast-enhanced and noncontrast images. It is an imaging procedure rather than a blood laboratory test.
Why might I need this test?
A CTA may be ordered to investigate symptoms such as sudden limb pain, chest pain, shortness of breath, weakness, or a pulsating abdominal mass. It can also be used to assess blood vessels before certain procedures or to monitor known vascular conditions.
How is the test performed?
You will lie on a CT table while an X-ray scanner takes pictures from different angles. For the contrast portion, contrast material is usually given through a vein in your arm, and the scan is timed to capture images as the contrast moves through your blood vessels.
How do I prepare for the test?
Follow the imaging center's specific instructions, as fasting may or may not be required. Tell the care team about any contrast allergy, kidney disease, pregnancy or possible pregnancy, and medications you take, because these factors may affect the protocol or safety of the contrast portion.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
The images may show narrowing or blockage of a blood vessel, an aneurysm, vessel wall injury, bleeding, or a blood clot. Comparing contrast and noncontrast images can help radiologists distinguish vessels from nearby tissues and identify abnormalities. The care team will interpret the findings together with your symptoms, examination, and any other tests.
Short name
CT angiogram with/without contrast
Frequently asked questions
Is a CT angiogram the same as a regular CT scan?
Will I receive contrast material?
Can I have this test if I am allergic to contrast or have kidney disease?
Sources
- 1
- 2Lab Tests OnlineSource
- 3
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.
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