SBIR-STTR Award

Shock wave lithotripsy (SWL) is the treatment of choice for kidney stones. Originally the standard lithotripter generated the shock with a sparker electrode, but their use has declined because the shocks are inconsistent, cause painful side effects and the electrode must be replaced during the procedure. New types of lithotripters are more consistent and last longer, but the clinical outcomes are not as good and side effects are greater. The goal of this research is to demonstrate the feasibility of a new type of spark electrode that produces consistent shocks, can reduce side effects and last for many procedures. The long-term goal is to develop a new commercial SWL, with reduced side effects and much longer life. The work will employ an innovative methodology and design algorithm for sparker electrodes used in Navy applications. The algorithm, developed for high energy shocks, will be scaled down for SWL. Experimental measurements using electrodes developed with this new methodology will be compared to an existing lithotripter to demonstrate improvements. A successful program will lead to a new commercial system for SWL that resolves the issues with current systems, resulting in improved clinical outcomes at lower cost. Public health may also benefit from use in additional medical applications, including healing bones, treatment of tendonitis and tumor therapy

Shock wave lithotripsy (SWL) is a non-invasive treatment for kidney stones and other ailments. However, current lithotripters produce painful side effects, and the mechanisms of lithotripsy and the causes of the side effects are not fully understood. Electrohydraulic lithotripters (EHL's), which use an underwater spark as a shock wave source, had been the treatment of choice but use has declined because the shocks are inconsistent, cause painful side effects and the electrodes are short lived. Typically, the electrode head wears out during a procedure, and must be replaced before completing the procedure. New types of lithotripters are more consistent and last longer than one procedure, but their clinical outcomes are reduced and side effects are greater. Phase I showed the feasibility of using a wire-initiated sparker to produce consistent and precise shocks, of controlling the shock (for potential improved comminution of kidney stones and reduction in side effects), of lasting for many procedures. The proposed Phase II continues research towards the long-term goal to develop a new commercial EHL that exceeds the clinical outcomes of lithotripters, with reduced side effects, much longer life and lower cost. The specific project objectives are to develop a wire feed system needed to employ wire- initiated sparkers for EHL, demonstrate ultra-long lifetime using the wire-feed, map out the acoustic field of the shock and cavitation in the focal region, conduct research using the sparker's varied shock waveforms to improve comminution of kidney stones and develop a prototype wire-feed sparker for commercialization. A successful project will result in improved clinical results of SWL at reduced cost. Shock wave lithotripsy (SWL) is a non-invasive treatment for kidney stones and other ailments. The electrodes in current systems must be replaced during a procedure, and the results are inconsistent, with unpleasant side effects. A successful program will result in a new SWL system with electrodes lasting several procedures, more consistent clinical outcomes, reduced side effects and lower cost .

Project Terms:
Acoustic; Acoustics; Address; Adverse effects; Au element; Biliary or Urinary Stones; CHRM3; CHRM3 gene; Calculi; Circulatory Collapse; Clinical; Collaborations; Development; Electrodes; Electromagnetic; Electromagnetics; Exhibits; Goals; Gold; HM3; Head; Investigators; Kidney Calculi; Kidney Stones; Legal patent; Length; Life; Litholapaxy; Lithotripsy; Maintenance; Maintenances; Maps; Marketing; Measurement; Measures; Mechanics; Names; Outcome; Output; Pain; Painful; Patents; Patients; Performance; Phase; Pressure; Pressure- physical agent; Procedures; Programs (PT); Programs [Publication Type]; Renal Calculi; Renal Stone; Reporting; Reproducibility; Research; Research Personnel; Researchers; Robin; Robin bird; SCHED; Schedule; Shock; Source; Spatial Distribution; Stone; System; System, LOINC Axis 4; Testing; Time; Translating; Translatings; Treatment Side Effects; Work; base; circulatory shock; commercialization; cost; design; designing; feeding; improved; language translation; meetings; nephrolith; pressure; professor; programs; prototype; side effect; therapy adverse effect; treatment adverse effect