Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2011 Feb;25(2):341-4.
doi: 10.1089/end.2010.0407. Epub 2010 Nov 22.

Histotripsy erosion of model urinary calculi

Alexander P Duryea  1 , Timothy L Hall, Adam D Maxwell, Zhen Xu, Charles A Cain, William W Roberts
Affiliations

Histotripsy erosion of model urinary calculi

Alexander P Duryea et al. J Endourol. 2011 Feb.

Abstract

Background and purpose: Histotripsy is a pulsed focused ultrasound technology in which initiation and control of acoustic cavitation allow for precise mechanical fractionation of tissues. The present study examines the feasibility of using histotripsy for erosion of urinary calculi.

Materials and methods: Histotripsy treatment was delivered from a 750-kHz transducer in the form of 5-cycle acoustic pulses at a 1-kHz pulse repetition frequency. Model stones were sonicated for 5 minutes at peak negative pressures (p-) of 10, 15, 19, 22, and 24-MPa. Resulting fragment sizes and comminution rates were assessed and compared with those achieved with a piezoelectric lithotripter (Wolf Piezolith 3000) operated at 2-Hz pulse repetition frequency and power level 17 (p- = 14-MPa).

Results: Histotripsy eroded the surface of stones producing fine (< 100 μm) particulate debris in contrast to the progressive and incomplete subdivision of stones achieved with piezoelectric lithotripsy. The histotripsy erosion rate increased with increasing peak negative pressure from 10 to 19 MPa and then saturated, yielding an average rate of 87.9 ± 12.8 mg/min at maximum treatment intensity. Piezoelectric lithotripsy achieved an average treatment rate of 110.7 ± 27.4 mg/min.

Conclusions: Histotripsy comminution of urinary calculi is a surface erosion phenomenon that is mechanistically distinct from conventional shockwave lithotripsy (SWL), producing only fine debris as opposed to coarse fragments. These characteristics suggest that histotripsy offers a potential adjunct to traditional SWL procedures, and synergistic interplay of the two modalities may lead to possible increases in both rate and degree of stone fragmentation.

PubMed Disclaimer

Figures

FIG. 1.
FIG. 1.
Ultracal-30 stone fragments following treatment with (a) histotripsy and (b) lithotripsy.
FIG. 2.
FIG. 2.
The histotripsy stone erosion rate plotted as a function of peak negative pressure (p-).
See this image and copyright information in PMC

References

    1. Soyupek S. Armagan A. Kosar A, et al. Risk factors for the formation of a steinstrasse after shock wave lithotripsy. Urol Int. 2005;74:323–325. - PubMed
    1. Osman MM. Alfano Y. Kamp S, et al. 5-year-follow-up of patients with clinically insignificant residual fragments after extracorporeal shockwave lithotripsy. Eur Urol. 2005;47:860–864. - PubMed
    1. El-Nahas AR. El-Assmy AM. Madbouly K. Sheir KZ. Predictors of clinical significance of residual fragments after extracorporeal shockwave lithotripsy for renal stones. J Endourol. 2006;20:870–874. - PubMed
    1. Zhu S. Cocks FH. Preminger GM. Zhong P. The role of stress waves and cavitation in stone comminution in shock wave lithotripsy. Ultrasound Med Biol. 2002;28:661–671. - PubMed
    1. Delius M. Minimal static excess pressure minimises the effect of extracorporeal shock waves on cells and reduces it on gallstones. Ultrasound Med Biol. 1997;23:611–617. - PubMed