CT Angiography, Thoracic Aortic Aneurysm, With and Without Intravenous Contrast
This CT scan uses contrast to examine the thoracic aorta and assess a possible aneurysm, helping evaluate its size and extent and guide treatment.
["The test helps doctors evaluate the thoracic aorta and determine the extent of an aneurysm or related blood-vessel problems."]
Key facts at a glance
- LOINC
- 87857-9
- Short code
- CTA TA + AA WO+W contr IV
- Synonyms
- CTA TA + AA WO+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
- ct-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?
CT angiography, or CTA, is an imaging test that uses X-ray images and intravenous contrast to examine blood vessels. In this case, it is used to evaluate the thoracic aorta, the main artery carrying blood from the heart through the chest, and look for an aortic aneurysm.
Why might I need this test?
This test may be ordered to assess a thoracic aortic aneurysm found on another imaging study or to monitor its size. It can also help evaluate nearby blood vessels, plan surgery or another procedure, or investigate symptoms such as sudden chest or back pain when other conditions are being considered.
How is the test performed?
You lie on a CT table while the scanner takes detailed pictures. If contrast is used, it is given through a vein in your arm, and the scan is timed to capture the arteries after the contrast circulates through the bloodstream.
How do I prepare for the test?
Follow the imaging center's instructions, as fasting or blood tests may be required in some cases. Tell the care team about prior contrast reactions, kidney disease, pregnancy, implanted devices, and medications such as metformin so they can provide appropriate instructions.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
The images can show the presence, size, and extent of an aneurysm and may identify aortic dissection, narrowing, calcification, or involvement of nearby vessels. These findings help determine the urgency of follow-up and may influence whether monitoring or a procedure is appropriate. The care team should interpret the results together with symptoms, medical history, and other imaging studies.
Short name
Thoracic aortic aneurysm CT angiography
Frequently asked questions
Is this the same as a routine CT scan?
Will I need an IV line?
What if I have kidney disease or a previous contrast reaction?
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