Phospholipids-coated Ultrasound Contrast Agents (UCA) may deflate or dissolve because of stress resulting from US-induced oscillations. In this work we investigate the behavior of isolated UCA during prolonged US excitation. An isolated UCA bubble was placed in a thin capillary tube and its oscillations were recorded using the Brandaris-128 camera while it was excited with hundreds of US pulses at low mechanical index. The results show that UCA undergo an irreversible, non destructive deflation process. Such deflation seems to occur in discrete steps rather than as a continuous process; furthermore, the oscillation of the bubble changes during deflation: both symmetric and asymmetric oscillations occur at various stages of the deflation process. Strongly asymmetric oscillations, such as compression-only and expansion-only, were also observed: notably, expansion-only is associated with a quick size reduction, whereas compressiononly mostly occurs when the bubble size does not change. These preliminary results indicate that bubble deflation might be resulting from at least two distinct phenomena, namely gas loss and material shed from the shell.

Non-uniform oscillations of deflating bubbles - a pilot study / J. Viti; R. Mori; F. Guidi; N De Jong; P. Tortoli. - ELETTRONICO. - (2011), pp. 652-655. (Intervento presentato al convegno 2011 IEEE Ultrasonics Symposium tenutosi a Orlando, FL, USA nel October 2011) [10.1109/ULTSYM.2011.6293538].

Non-uniform oscillations of deflating bubbles - a pilot study

VITI, JACOPO;MORI, RICCARDO;GUIDI, FRANCESCO;TORTOLI, PIERO
2011

Abstract

Phospholipids-coated Ultrasound Contrast Agents (UCA) may deflate or dissolve because of stress resulting from US-induced oscillations. In this work we investigate the behavior of isolated UCA during prolonged US excitation. An isolated UCA bubble was placed in a thin capillary tube and its oscillations were recorded using the Brandaris-128 camera while it was excited with hundreds of US pulses at low mechanical index. The results show that UCA undergo an irreversible, non destructive deflation process. Such deflation seems to occur in discrete steps rather than as a continuous process; furthermore, the oscillation of the bubble changes during deflation: both symmetric and asymmetric oscillations occur at various stages of the deflation process. Strongly asymmetric oscillations, such as compression-only and expansion-only, were also observed: notably, expansion-only is associated with a quick size reduction, whereas compressiononly mostly occurs when the bubble size does not change. These preliminary results indicate that bubble deflation might be resulting from at least two distinct phenomena, namely gas loss and material shed from the shell.
2011
2011 IEEE Ultrasonics Symposium Proceedings
2011 IEEE Ultrasonics Symposium
Orlando, FL, USA
October 2011
J. Viti; R. Mori; F. Guidi; N De Jong; P. Tortoli
File in questo prodotto:
Non ci sono file associati a questo prodotto.

I documenti in FLORE sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificatore per citare o creare un link a questa risorsa: https://hdl.handle.net/2158/787528
Citazioni
  • ???jsp.display-item.citation.pmc??? ND
  • Scopus 0
  • ???jsp.display-item.citation.isi??? 1
social impact