Effect of lithotripter focal width on stone comminution in shock wave lithotripsy.
Abstract
Using a reflector insert, the original HM-3 lithotripter field at 20 kV was altered
significantly with the peak positive pressure (p(+)) in the focal plane increased
from 49 to 87 MPa while the -6 dB focal width decreased concomitantly from 11 to 4
mm. Using the original reflector, p(+) of 33 MPa with a -6 dB focal width of 18 mm
were measured in a pre-focal plane 15-mm proximal to the lithotripter focus. However,
the acoustic pulse energy delivered to a 28-mm diameter area around the lithotripter
axis was comparable ( approximately 120 mJ). For all three exposure conditions, similar
stone comminution ( approximately 70%) was produced in a mesh holder of 15 mm after
250 shocks. In contrast, stone comminution produced by the modified reflector either
in a 15-mm finger cot (45%) or in a 30-mm membrane holder (14%) was significantly
reduced from the corresponding values (56% and 26%) produced by the original reflector
(no statistically significant differences were observed between the focal and pre-focal
planes). These observations suggest that a low-pressure/broad focal width lithotripter
field will produce better stone comminution than its counterpart with high-pressure/narrow
focal width under clinically relevant in vitro comminution conditions.
Type
Journal articleSubject
AcousticsCalculi
Equipment Design
Lithotripsy
Materials Testing
Models, Theoretical
Motion
Phantoms, Imaging
Pressure
Time Factors
Transducers, Pressure
Permalink
https://hdl.handle.net/10161/4244Published Version (Please cite this version)
10.1121/1.3308409Publication Info
Qin, Jun; Simmons, W Neal; Sankin, Georgy; & Zhong, Pei (2010). Effect of lithotripter focal width on stone comminution in shock wave lithotripsy.
J Acoust Soc Am, 127(4). pp. 2635-2645. 10.1121/1.3308409. Retrieved from https://hdl.handle.net/10161/4244.This is constructed from limited available data and may be imprecise. To cite this
article, please review & use the official citation provided by the journal.
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Show full item recordScholars@Duke
Walter Neal Simmons
Gendell Family Professor of the Practice
Pei Zhong
Professor in the Thomas Lord Department of Mechanical Engineering and Materials Science
My research focuses on engineering and technology development with applications in
the non-invasive or minimally invasive treatment of kidney stone disease via shock
wave and laser lithotripsy, high-intensity focused ultrasound (HIFU) and immunotherapy
for cancer treatment, acoustic and optical cavitation, and ultrasound neuromodulation
via sonogenetics.
We are taking an integrated and translational approach that combines fundamental research
with engineering and applied technol
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