Abstract
The field of contrast-enhanced ultrasound (CEUS) combines nonlinearly oscillating microbubbles (MBs) with dedicated pulse sequences to reveal the vascular function of organs. Clinical ultrasound contrast agents consist of polydisperse MB suspensions with diameters ranging from 0.5 to 10 μm and resonance frequencies ranging from 1 to 15 MHz. As a result, just a small fraction of MBs resonates at a given ultrasound frequency. MB suspensions with narrow size distributions can be tuned for a specific imaging frequency, boost CEUS sensitivity, and enable deeper vascular imaging. However, their enhanced nonlinear behavior makes imaging susceptible to nonlinear-wave-propagation artifacts. Here we numerically investigate the impact of the acoustic wavefront shape on the imaging of nonlinearly oscillating, monodisperse MBs. Specifically, our approach relies on an extension of the iterative nonlinear-contrast-source method that accounts for all nonlinear effects in CEUS. We demonstrate that supersonic X-shaped wavefronts referred to as “X waves” can be used to generate ultrasound images of monodisperse MBs without nonlinear-wave-propagation artifacts. In contrast, imaging based on focused, planar, and diverging wavefronts leads to significant nonlinear artifacts. Taken together, our results show that X waves can harness the full potential of monodisperse MBs by enabling their sensitive and specific detection in a tissue context.
Original language | English |
---|---|
Article number | 034062 |
Number of pages | 12 |
Journal | Physical Review Applied |
Volume | 22 |
Issue number | 3 |
DOIs | |
Publication status | Published - 2024 |
Bibliographical note
Green Open Access added to TU Delft Institutional Repository 'You share, we take care!' - Taverne project https://www.openaccess.nl/en/you-share-we-take-careOtherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public.
Keywords
- Condensed Matter, Materials & Applied Physics
- Interdisciplinary Physics