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dc.contributor.advisorCleveland, Robin O.en_US
dc.contributor.authorChitnis, Parag Vijayen_US
dc.date.accessioned2010-11-04T20:28:12Z
dc.date.available2007-11-04T20:28:12Z
dc.date.issued2007
dc.identifier.urihttps://hdl.handle.net/2144/1363
dc.description.abstractShock wave lithotripsy is the preferred treatment modality for kidney stones in the United States. Despite clinical use for over twenty-five years, the mechanisms of stone fragmentation are still under debate. A piezoelectric array was employed to examine the effect of waveform shape and pressure distribution on stone fragmentation in lithotripsy. The array consisted of 170 elements placed on the inner surface of a 15 cm-radius spherical cap. Each element was driven independently using a 170 individual pulsers, each capable of generating 1.2 kV. The acoustic field was characterized using a fiber optic probe hydrophone with a bandwidth of 30 MHz and a spatial resolution of 100 μm. When all elements were driven simultaneously, the focal waveform was a shock wave with peak pressures p+ =65±3MPa and p−=−16±2MPa and the −6 dB focal region was 13 mm long and 2 mm wide. The delay for each element was the only control parameter for customizing the acoustic field and waveform shape, which was done with the aim of investigating the hypothesized mechanisms of stone fragmentation such as spallation, shear, squeezing, and cavitation. The acoustic field customization was achieved by employing the angular spectrum approach for modeling the forward wave propagation and regression of least square errors to determine the optimal set of delays. Results from the acoustic field customization routine and its implications on stone fragmentation will be discussed.en_US
dc.description.sponsorshipNational Institutes of Health DK043881en_US
dc.language.isoen_US
dc.rightsAttribution 3.0 Unporteden_US
dc.rights.urihttp://creativecommons.org/licenses/by/3.0/
dc.subjectShock wave lithotripsyen_US
dc.subjectAcousticsen_US
dc.subjectInversionen_US
dc.titleA study of stone fragmentation in shock wave lithotripsy by customizing the acoustic field and waveform shapeen_US
dc.typeThesis/Dissertationen_US
etd.degree.nameDoctor of Philosophyen_US
etd.degree.leveldoctoralen_US
etd.degree.disciplineMechanical Engineeringen_US
etd.degree.grantorBoston Universityen_US


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Attribution 3.0 Unported
Except where otherwise noted, this item's license is described as Attribution 3.0 Unported