Abstract
Two 5 mm by 5 mm square aluminum lenses with a 6 mm depth of focus were machined and tested for histotripsy with a 40% volume fraction 1-3 PZT-5A composite and a Meggitt Pz-39 porous ceramics lapped to 315 $\mu \text{m}$ as the piezoelectric elements. The devices were air-backed, and an 89 $\mu \text{m}$ layer of Parylene-C was deposited on the lens, matching aluminum to water. Both devices were driven single-ended at 5.8 MHz, their optimal frequency after bonding to the lens, with ten cycles at a PRF of 1 kHz. The composite-based device showed no sign of free-field cavitation in water up to a drive level of 600 V, whereas the Pz39-based device was able to cavitate in water at a drive level of 220 V. In vivo ablation of a rat brain tissue was demonstrated through an opening in the skull and required the drive voltage be increased to 280 V. The ablation was monitored using B-mode imaging with an endoscopic 30 MHz ultrasound phased array and power Doppler overlay. Ablation was maintained for 12 s and, in the power Doppler image, the ablation zone grew steadily over this time to 1.9 mm by 3.4 mm. Immediately after treatment, the ablated area appeared anechoic, slowly filling with specular material.
Original language | English |
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Pages (from-to) | 1442-1451 |
Number of pages | 10 |
Journal | IEEE Transactions on Ultrasonics, Ferroelectrics, and Frequency Control |
Volume | 69 |
Issue number | 4 |
DOIs | |
Publication status | Published - Apr 1 2022 |
Bibliographical note
Publisher Copyright:© 1986-2012 IEEE.
ASJC Scopus Subject Areas
- Instrumentation
- Acoustics and Ultrasonics
- Electrical and Electronic Engineering
PubMed: MeSH publication types
- Journal Article
- Research Support, Non-U.S. Gov't