A carotid intima-media thickness scan measures the thickness of the carotid arteries’ inner walls. Ultrasound imaging of the carotid arteries can also reveal the presence of plaque, which increases the patient’s risk of stroke. The most common cause of thickening of the intima media is atherosclerosis. It is not, however, the only cause.
The data produced by the IMT imaging allows the interpreting physician to compare the average thickness of the patient’s intima media against that of the intima-media thickness of people the same age and gender to arrive at an arterial “age” for the patient. IMT scans can be performed on arteries other than the carotid, but carotid IMT scans are generally considered the standard. In an IMT assessment, only conventional ultrasound imaging (B-mode) is employed; Doppler imaging is not needed because blood-flow velocity is not relevant to what is being measured.
The procedure is safe and painless. The IMT scan should take about 15 to 20 minutes.
Common indications for ordering an IMT scan include:
- Family History of Cardiovascular Disease
- Post-Heart Attack or Post-Stroke Monitoring
- Tobacco Use
- Obesity (BMI >30)
- High LDL or Low HDL Cholesterol Levels
- A Positive EBT Calcium Score
- Elevated Lipoprotein(a)
- Sedentary Lifestyle