Table 1:

Intimal atherosclerosis classifications

Grade	Severity	Katz [20]	ASE/EACVI guideline [21]
I	Normal	Normal aorta	Intimal thickness <2 mm
II	Mild	Extensive intimal thickening	Focal or diffuse intimal thickness 2–3 mm
III	Moderate	Sessile atheroma extending <5 mm into the lumen	3–5 mm (no mobile/ulcerated components)
IV	Severe	Sessile atheroma protruding >5 mm (protruding atheroma)	>5 mm (no mobile/ulcerated components)
V		Mobile atheroma	Complex grade 2–4 atheroma plus mobile or ulcer