Intima-Media Thickness (IMT): B-mode ultrasound measurement of the combined intimal and medial carotid wall thickness; a marker of subclinical atherosclerosis and cardiovascular risk.
Carotid intima-media thickness (IMT) is the combined thickness of the intimal and medial layers of the carotid artery wall measured on B-mode ultrasound. It is a validated surrogate marker of subclinical atherosclerosis and cardiovascular risk. Normal IMT is <0.9 mm; values >1.0 mm indicate borderline increased cardiovascular risk, and focal thickening >1.5 mm is classified as plaque.