Figure 2.

Left: P and DS sections stained with (a) Masson’s trichrome stain, (b) α-SMA and (c) CD68 immunostain (original magnification 2×, insets 10×). P is a type VI plaque with a necrotic core, calcifications, intraplaque thrombus and a thin fibrous cap composed of collagen and αSM-actin positive cells; minor intraplaque CD68 positive staining is present and α-SMA -actin positive contractile VSMCs are also visible on the outer border of the specimen (opposite to the lumen) due to surgical cleavage of plaque from the intact tunica media. In DS, a much thinner lesion (equivalent to Stary type III) with extensive α -SMA and CD68 cellular positivity is present. Right: From top to bottom. Average values and SD of lesional area (mm²), intralesional α-SMA and CD68 stain positivity (% of lesional area) of P and DS segments of all specimens’ sections: a smaller lesional area and a markedly higher positivity of both cellular markers in the distal side of the plaque is evident (*p<0.05, **p<0.02 paired t-test).