On the potential of a new IVUS elasticity modulus imaging approach for detecting vulnerable atherosclerotic coronary plaques: in vitro vessel phantom study

Phys Med Biol. 2010 Oct 7;55(19):5701-21. doi: 10.1088/0031-9155/55/19/006. Epub 2010 Sep 8.

Abstract

Peak cap stress amplitude is recognized as a good indicator of vulnerable plaque (VP) rupture. However, such stress evaluation strongly relies on a precise, but still lacking, knowledge of the mechanical properties exhibited by the plaque components. As a first response to this limitation, our group recently developed, in a previous theoretical study, an original approach, called iMOD (imaging modulography), which reconstructs elasticity maps (or modulograms) of atheroma plaques from the estimation of strain fields. In the present in vitro experimental study, conducted on polyvinyl alcohol cryogel arterial phantoms, we investigate the benefit of coupling the iMOD procedure with the acquisition of intravascular ultrasound (IVUS) measurements for detection of VP. Our results show that the combined iMOD-IVUS strategy: (1) successfully detected and quantified soft inclusion contours with high positive predictive and sensitivity values of 89.7 ± 3.9% and 81.5 ± 8.8%, respectively, (2) estimated reasonably cap thicknesses larger than ∼300 µm, but underestimated thinner caps, and (3) quantified satisfactorily Young's modulus of hard medium (mean value of 109.7 ± 23.7 kPa instead of 145.4 ± 31.8 kPa), but overestimated the stiffness of soft inclusions (mean Young`s moduli of 31.4 ± 9.7 kPa instead of 17.6 ± 3.4 kPa). All together, these results demonstrate a promising benefit of the new iMOD-IVUS clinical imaging method for in vivo VP detection.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Algorithms
  • Biomechanical Phenomena
  • Coronary Vessels / diagnostic imaging*
  • Coronary Vessels / injuries
  • Coronary Vessels / pathology
  • Coronary Vessels / physiopathology*
  • Elastic Modulus*
  • Humans
  • Image Processing, Computer-Assisted
  • Models, Biological
  • Necrosis / diagnostic imaging
  • Necrosis / pathology
  • Necrosis / physiopathology
  • Nonlinear Dynamics
  • Phantoms, Imaging*
  • Plaque, Atherosclerotic / diagnostic imaging*
  • Plaque, Atherosclerotic / pathology
  • Plaque, Atherosclerotic / physiopathology*
  • Polyvinyl Alcohol
  • Reproducibility of Results
  • Rupture / diagnostic imaging
  • Rupture / pathology
  • Rupture / physiopathology
  • Ultrasonography, Interventional / instrumentation*

Substances

  • Polyvinyl Alcohol