Carotid Artery Intima-Media Thickness (IMT) Measurement, Neck Vessel
This test measures the thickness of the inner lining of your carotid arteries—a key indicator of plaque buildup, often linked to atherosclerosis. It helps assess risk for heart attack or stroke.
["A simple ultrasound test to check artery health and prevent serious cardiovascular events."]
Key facts at a glance
- LOINC
- 30859-3
- Short code
- MRA Carotid ves+Neck ves
- Synonyms
- MRA Carotid ves+Neck ves
- Category
- chemistry
- Sample
- serum
- Container
- Red-top tube (SST)
- Units
- N/A
- Ref low
- 22
- Ref high
- 198
- Critical range
- — – 10000 N/A
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- 18–65 years
- Method
- mr-angio
- CPT
- 82553
- 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
Why This Test Matters: Your Health Risk
Carotid IMT evaluates how thick the artery walls are in your neck. Thicker walls may signal early plaque formation, which can restrict blood flow and increase risks like heart disease or stroke. This test is often used alongside other vascular assessments to guide preventive care.
How the Test Works
No special preparation is needed. A technician applies gel to your neck and uses ultrasound waves to measure the distance between your artery’s inner and outer layers. The process is painless and takes about 15 minutes.
What to Expect During the Procedure
You’ll lie down comfortably while the technician moves a handheld device (probe) gently over your neck. You may hear a clicking sound as the ultrasound waves create images of your arteries. No needles or radiation are involved.
Common Reasons for This Test
Doctors order carotid IMT testing if you have risk factors like high blood pressure, high cholesterol, diabetes, smoking history, or a family history of vascular disease. It may also be used to monitor treatment progress for known artery disease.
Reference range
Adult males: 22-198 U/L; Females: 22-198 U/LN/A
No special preparation required. Inform provider of any chest pain or symptoms.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
Thinner-than-expected IMT may suggest healthy arteries, while thicker measurements could indicate early atherosclerosis. Results help doctors determine if lifestyle changes, medications, or further testing (like a carotid ultrasound) are needed to manage your risk. This test is particularly useful for identifying subtle changes before symptoms appear.
Short name
Carotid IMT
Frequently asked questions
What does a high carotid IMT mean?
How often should I get this test?
Can I eat or drink before this test?
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 17, 2026. · Read our editorial policy