Finite element HIFU transducer acoustic field modeling evaluation with measurements

Abstract

This paper presents the finite element modeling of the acoustic pressure spatial distribution of a spherically-curved transducer with operation frequency of 1.965 MHz and its comparison with the transducer characterization using a PZTZ44-0400 hydrophone. Concave transducers are only one of the different techniques used to deliver high-intensity focused ultrasound (HIFU) into a target during oncologic treatments in order to provoke tumor ablation. However, the acoustic field characterization for HIFU transducers is made at low power level in order to avoid hydrophone damage, while in therapy high acoustic power is applied. HIFU focus size is usually in the order of mm, making difficult its location during experimentation. Finite element modeling is helpful method to simulate focused ultrasound propagation and interaction in a simulated medium with ultrasonic properties similar to soft tissues. In this work, comparison is made in water as propagation wave medium.