The ultrasound contrast agents used in echographic imaging techniques are essentially constituted by a suspension of microbubbles containing gas enclosed within an organic shell. In the present paper, the elastic characteristics of contrast agents have been studied, as they depend upon the temperature, using a photoacoustic technique. Central element of the experimental apparatus is a photoacoustic cell, where the ultrasound contrast agent is inserted and behaves as a Helmholtz resonator. A laser radiation modulated at frequencies in the range 100-1500 Hz, causes the solution volume containing the bubbles to vary; this causes thin membrane, which closes a small pipe inserted on the surface of the photoacoustic cell, to vibrate. The amplitude variations of the membrane, measured through a laser probe interferometer, vs. bubble concentration and temperature of the solution, allow one to investigate microbubbles thermal behavior.
thermal behavior of ultrasound contrast agents for echographic imaging techniques through a photoacoustic system / Alippi, Adriano; Bettucci, Andrea; Biagioni, Angelo; Conclusio, Davide; D'Orazio, Annunziata; Germano, Massimo; Passeri, Daniele. - STAMPA. - (2010), pp. 103-1-103-8. (Intervento presentato al convegno EAA EUROREGIO 2010 1st European Congress on Sound and Vibration tenutosi a Ljubljana, Slovenia nel 15-18 Settembre 2010).
thermal behavior of ultrasound contrast agents for echographic imaging techniques through a photoacoustic system
ALIPPI, Adriano;BETTUCCI, Andrea;BIAGIONI, ANGELO;CONCLUSIO, DAVIDE;D'ORAZIO, Annunziata;GERMANO, Massimo;PASSERI, Daniele
2010
Abstract
The ultrasound contrast agents used in echographic imaging techniques are essentially constituted by a suspension of microbubbles containing gas enclosed within an organic shell. In the present paper, the elastic characteristics of contrast agents have been studied, as they depend upon the temperature, using a photoacoustic technique. Central element of the experimental apparatus is a photoacoustic cell, where the ultrasound contrast agent is inserted and behaves as a Helmholtz resonator. A laser radiation modulated at frequencies in the range 100-1500 Hz, causes the solution volume containing the bubbles to vary; this causes thin membrane, which closes a small pipe inserted on the surface of the photoacoustic cell, to vibrate. The amplitude variations of the membrane, measured through a laser probe interferometer, vs. bubble concentration and temperature of the solution, allow one to investigate microbubbles thermal behavior.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
