Signal processing strategy for the exploitation of ultrasound contrast agents by current medical instrumentation

A correct exploitation of an ultrasound contrast agent injected into the human body and the measurement of the nonlinear responses generated by the bubbles that form it need an acoustic insonification beam having a quasi-constant pressure profile over a large depth interval. In order to obtain this special beam, a stochastic method of synthesis (based on simulated annealing), aimed at the optimization of the weight coefficients to be applied to the array transducers, has been developed and assessed. The results obtained in terms of pressure profile and simulated echographic images are reported and discussed.

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