Endovascular shear strain elastography for the detection and characterization of the severity of atherosclerotic plaques: in vitro validation and in vivo evaluation

Ultrasound Med Biol. 2014 May;40(5):890-903. doi: 10.1016/j.ultrasmedbio.2013.12.008. Epub 2014 Feb 2.


This work explores the potential of shear strain elastograms to identify vulnerable atherosclerotic plaques. The Lagrangian speckle model estimator (LSME) elasticity imaging method was further developed to estimate shear strain elasticity (SSE). Three polyvinyl alcohol cryogel vessel phantoms were imaged with an intravascular ultrasound (IVUS) scanner. The estimated SSE maps were validated against finite-element results. Atherosclerosis was induced in carotid arteries of eight Sinclair mini-pigs using a combination of surgical techniques, diabetes and a high-fat diet. IVUS images were acquired in vivo in 14 plaques before euthanasia and histology. All plaques were characterized by high magnitudes in SSE maps that correlated with American Heart Association atherosclerosis stage classifications (r = 0.97, p < 0.001): the worse the plaque condition the higher was the absolute value of SSE, i.e. |SSE| (e.g., mean |SSE| was 3.70 ± 0.40% in Type V plaques, whereas it was reduced to 0.11 ± 0.01% in normal walls). This study indicates the feasibility of using SSE to highlight atherosclerotic plaque vulnerability characteristics.

Keywords: Atherosclerotic plaque image processing; Intravascular ultrasound; Shear strain; Swine model; Vascular elastography; Vulnerable plaques.

Publication types

  • Research Support, Non-U.S. Gov't
  • Validation Study

MeSH terms

  • Animals
  • Carotid Arteries / diagnostic imaging*
  • Disease Models, Animal
  • Elasticity Imaging Techniques / methods*
  • Feasibility Studies
  • Image Interpretation, Computer-Assisted / methods
  • Image Processing, Computer-Assisted / methods
  • Male
  • Phantoms, Imaging
  • Plaque, Atherosclerotic / diagnostic imaging*
  • Severity of Illness Index
  • Stress, Mechanical*
  • Swine
  • Swine, Miniature
  • Ultrasonography, Interventional / methods*