Table 2.

AHA classification and AHA-MR based classification from reference 31

	AHA classification	Carotid MR-based AHA classification from Cai et al
Type I	Initial lesion with foam cells	Near-normal wall thickness, no calcification
Type II	Fatty streak with multiple foam cell layers
Type III	Pre-atheroma with extracellular lipid pools	Diffuse intimal thickening or small eccentric plaque with no calcification
Type IV	Atheroma with a confluent extracellular lipid core	Plaque with a lipid or necrotic core surrounded by fibrous tissue with possible calcification
Type V	Fibroatheroma
Type VI	Complex plaque with possible surface defect, hemorrhage, or thrombus	Complex plaque with possible surface defect, hemorrhage, or thrombus
Type VII	Calcified plaque	Calcified plaque
Type VIII	Fibrotic plaque without lipid core	Fibrotic plaque without lipid core and with possible small calcifications