Benchtop and Initial Clinical Evaluation of the ShockPulse Stone Eliminator in Percutaneous Nephrolithotomy

Abstract

Purpose: Standardized bench testing of the new ShockPulse™ intracorporeal lithotripter was performed against three commercially available lithotripsy systems to determine differences and nuances in performance.

Materials and methods: The ShockPulse intracorporeal lithotripter was tested against the LUS-2™, CyberWand,™ and EMS LithoClast™ in a standardized bench setting using hard (Ultracal-30) and soft (plaster of Paris) stone phantoms. An in vitro kidney model was used to record the time needed to fragment stone samples into retrievable-sized pieces. The time needed to fully comminute and evacuate stone samples was also recorded. The efficacy of each device at various applied pressures was determined using a hands-free apparatus, which was used to apply 1.0, 1.5, and 2.0 pounds of fixed force.

Results: For hard and soft stones, the time needed to create retrievable fragments was similar among all systems (p = 0.585). The ShockPulse was significantly faster than the LUS-2 and LithoClast at fully fragmenting and evacuating stone samples (p = 0.046), while the CyberWand was significantly slower than all three systems at this task (p = 0.001). When fixed forces were applied to a large stone phantom, the ShockPulse and CyberWand were significantly faster than the LUS-2 and LithoClast (p < 0.0001). When groups of smaller stones were tested, the ShockPulse was significantly faster at 1.0 pound (p < 0.001) and 1.5 pounds (p < 0.002) of force. At 2.0 pounds, no differences were observed (p = 0.09).

Conclusions: The ShockPulse is equally as effective and, in some circumstances, more effective than the three commercially available devices against which it was tested in an in vitro setting.

Keywords: intracorporeal lithotripsy; percutaneous nephrolithotomy; urolithiasis.