Enhanced targeting of ultrasound contrast agents using acoustic radiation force

Ultrasound Med Biol. 2007 Jul;33(7):1132-9. doi: 10.1016/j.ultrasmedbio.2007.01.005. Epub 2007 Apr 18.

Abstract

Contrast-enhanced ultrasound has shown significant promise as a molecular imaging modality. However, one potential drawback is the difficulty that ultrasound contrast agents (UCA) may have in achieving adhesion to target molecules on the vascular endothelium. Microbubble UCA exhibit a lateral migration toward the vessel axis in laminar flow, preventing UCA contact with the endothelium. In the current study, we have investigated low-amplitude acoustic radiation as a mechanism to move circulating UCA toward targeted endothelium. Intravital microscopy was used to assess the retention of microbubble UCA targeted to P-selectin in the mouse cremaster microcirculation and femoral vessels. Acoustic treatment enhanced UCA retention to P-selectin four-fold in cremaster venules and in the femoral vein and 20-fold in the femoral artery. These results suggest acoustic treatment as a mechanism for enabling ultrasound-based molecular imaging in blood vessels with hemodynamic and anatomical conditions otherwise adversarial for UCA retention.

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • Abdominal Muscles / blood supply
  • Animals
  • Cell Adhesion
  • Endothelium, Vascular / chemistry
  • Femoral Artery / chemistry
  • Femoral Vein / chemistry
  • Fluorocarbons
  • Leukocytes / chemistry
  • Male
  • Mice
  • Mice, Inbred C57BL
  • Mice, Knockout
  • Microbubbles*
  • Microcirculation
  • Models, Animal
  • P-Selectin
  • Particle Size
  • Ultrasonics*
  • Ultrasonography / methods

Substances

  • Fluorocarbons
  • P-Selectin
  • perfluorobutane