Characterization of a needle hydrophone array for acoustic feedback during ultrasound hyperthermia treatments

Abstract

A prototype 16-element needle hydrophone array has been designed, fabricated and characterized. The primary use of this array is to provide acoustic feedback during ultrasound hyperthermia treatments. This feedback is necessary to compensate phased array heating patterns for patient motion and tissue inhomogeneities in real time. The array consists of a PVDF covered silicon substrate carrier which contains the signal electrodes of the individual acoustic sensors. Tests have shown that the array is sensitive to both pulsed and continuous ultrasound (943 kHz) excitation and can be used in tissue media. A complete description of the needle array, element cross-coupling measurements, beam profile measurements, calibration procedures and sensitivity analyses in both water and tissue are presented.

A hybrid computational model for ultrasound phased-array heating in presence of strongly scattering obstacles

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