Skip to main content
. Author manuscript; available in PMC: 2014 Dec 1.
Published in final edited form as: IEEE Trans Ultrason Ferroelectr Freq Control. 2013 Dec;60(12):2471–2487. doi: 10.1109/TUFFC.2013.2847

Figure 4.

Figure 4

Three examples of ARFI images with matched histology. Stains include: hematoxylin and eosin (H&E) (shown in (a.1), (b.1), and (c.1)); Lillie’s modified Masson's trichrome (LMT) staining collagen blue (shown in (a.2), (b.2), and (c.2)); Von Kossa (VK) staining calcium black (shown in (a.3) and (b.3)); and Verhoeff-Van Gieson (VVG) staining elastin black (shown in (c.3)). Black arrows are used to indicate plaque features (C = calcium, L = lipid, F = fibrous cap or fibrosis). In (a), an advanced Type Vb atheroma, spanning a lateral range of approximately −7.5 to −2.5 mm, is seen with a large calcium deposit located to the left part of a lipid pool. ARFI peak displacement image (a.4), taken with SP3-ParRx, shows an area of low displacement (blue) indicating a stiff material spatially matching the area of calcium, and an area of high peak displacement (red) indicating a soft material spatially matching the area of lipid pool. An area of slightly lower displacement (compared to the lipid pool) spans the top of the plaque in the position of the fibrous cap. In (b), an advanced type Vb atheroma, spanning a lateral range of approximately −5 to 0 mm, is seen with a large calcium deposit underneath a small lipid pool and fibrous cap. ARFI peak displacement image (b.4), taken with SP3-SRx, shows an area of low displacement (green/blue pixels) indicating a stiff material spatially matching the extent of the calcium deposition. An area of slightly elevated displacement is seen just above the area of low displacement, which spatially correlates with the small lipid pool and fibrous cap above the calcium. In (c), a type IV plaque spans the lateral range of −5 to 1 mm, with significant collagen deposition. The ARFI peak displacement image, taken with SP1.5-ParRx, shows a substantial decrease in peak displacement (blue) spatially aligned with the area of fibrosis. The ARFI recovery time image shows a gradient of increased recovery time across the plaque spatially located in areas where the IEL has started to degrade and duplicate. Zoomed in VVG images ((c.3.1), (c.3.2), and (c.3.3)) show the degraded IEL at three points along the artery, in areas where the recovery time is fast (~0.2 msec), slow (~0.8 msec), and moderate (~0.6 msec), respectively. In (c.3.1) the IEL is duplicated but generally intact, and RT is fast; in (c.3.2) the IEL is substantially disrupted and chaotic, and RT is slow; and in (c.3.3) the IEL is somewhat degraded, and RT is slightly faster than in (c.3.2).