Lithotripsy

Abstract

Shock wave lithotripsy (SWL) is the process of fragmentation of renal or ureteric stones by the use of repetitive shock waves generated outside the body and focused onto the stone. Following its introduction in 1980, SWL revolutionized the treatment of kidney stones by offering patients a non-invasive procedure. It is now seen as a mature technology and its use is perceived to be routine. It is noteworthy that, at the time of its introduction, there was a great effort to discover the mechanism(s) by which it works, and the type of sound field that is optimal. Although nearly three decades of subsequent research have increased the knowledge base significantly, the mechanisms are still controversial. Furthermore there is a growing body of evidence that SWL results in injury to the kidney which may have long-term side effects, such as new onset hypertension, although again there is much controversy within the field. Currently, use of lithotripsy is waning, particularly with the advent of minimally invasive ureteroscopic approaches. The goal here is to review the state of the art in SWL and to present the barriers and challenges that need to be addressed for SWL to deliver on its initial promise of a safe, effective, non-invasive treatment for kidney stones.

Numerical simulation of the nonlinear ultrasonic pressure wave propagation in a cavitating bubbly liquid inside a sonochemical reactor

“…The use of ultrasound is beneficial in many engineering applications such as cleaning of medical devices [1], treatment of waste water [2], textile cleaning [3], and fragmentation of ureteric and kidney stones [4]. As reviewed by Gogate [5] and Mason [6], the applications can vary from microscale setups for crystallization, polymer chemistry (for initiation of reactions or for destruction of complex polymer structures) and intercellular protein recovery to industrial operations such as refining of fossil fuels, extraction of coal tars, air cleaning as well as removal of biological/chemical contamination.…”

Prediction of far-field acoustic emissions from cavitation clouds during shock wave lithotripsy for development of a clinical device

“…With current apparatus, the clinician is ill-equipped to determine in-theatre whether the treatment has been successful, with the result that 30-50% of patients need to return for re-treatment, and an unknown number receive a greater exposure to shock waves than is necessary for stone fragmentation [2]. Overexposure carries the potential for adverse side effects [3][4][5][6].…”

“…Such a case is studied here, simulating the responses of bubbles subjected to shock waves generated by SWL [1,2]. The technique is however equally applicable to scenarios involving underwater explosions or industrial erosion, which might be undesirable [8] or required, as with ultrasonic cleaning [9,10].…”

“…Following successful clinical trials where its automated response proved to have 94.7 per cent sensitivity in predicting a successful patient outcome, compared with 36.8 per cent achieved by the clinician performing the treatment [18], this device is currently being used for real-time assessment of treatment in the clinic (a typical lithotripsy treatment lasts about an hour). It is also being tested for its ability to predetermine whether a kidney stone will be susceptible to SWL or whether the patient should be referred instead for some other form of stone treatment [2,19].…”

Characterizing shock waves in hydrogel using high speed imaging and a fiber-optic probe hydrophone

“…Shock waves are ubiquitous in nature and play an important role in a variety of scientific processes and industrial applications such as equation of state (EOS) measurements, [1][2][3] medical treatments, 4,5 explosives, 6,7 droplet impact studies, [8][9][10] cavitation studies, 6,7,11 and material characterization. Techniques for reproducibly generating and characterizing shocks enable the improved understanding of relevant physics and facilitate the application of shock phenomena to problems in science and technology.…”