A Modular, Kerf-Minimizing Approach for Therapeutic Ultrasound Phased Array Construction

IEEE Trans Ultrason Ferroelectr Freq Control. 2022 Oct;69(10):2766-2775. doi: 10.1109/TUFFC.2022.3178291. Epub 2022 Sep 27.

Abstract

A novel method for fabricating a modular, kerf-minimizing histotripsy phased array was developed and tested. The method utilizes arbitrarily shaped elements, 3-D printing, water jet cutting, and a thin, 125- [Formula: see text] electrically insulating epoxy coating to maximize aperture utilization while allowing for replacement of individual transducer modules. The method was used to fabricate a 750-kHz truncated circular aperture array (165 mm ×234 mm) transducer with a focal length of 142 mm. The aperture was segmented into 260 arc-shaped modular elements, each approximately 11.5 mm ×11.5 mm, arranged in concentric rings. The resulting aperture utilization was 92%. The full-width-half-maximum (FWHM) focal zone of the array was measured to be 1.6 mm ×1.1 mm ×4.5 mm, and the FWHM electrical steering range was measured to be 38.5 mm ×33 mm 40 mm. The array was estimated to be capable of generating approximately 120-MPa peak negative pressure at the geometric focus. In addition, the array was used to ablate a 5-cm3 volume of tissue with electric focal steering.

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • Transducers
  • Ultrasonic Therapy* / methods
  • Water

Substances

  • Water