Patent ID: 8535250

Claim:
A method for detecting the fragmentation of a kidney stone during shock wave therapy, the method comprising the steps of: (a) detecting a resonant acoustic scattering wave to generate a resonant acoustic scattering signal during therapy, the resonant acoustic scattering signal being indicative of internal stress vibrations in the kidney stone, where the internal stress vibrations are in response to shock waves impacting the kidney stone; (b) processing the resonant acoustic scattering signal to determine a frequency spectrum of the stress vibrations, the processing comprising determining a frequency spectrum of the stress vibrations induced by an initial shock wave, and determining a frequency spectrum of the stress vibrations induced by at least one subsequent shock wave; and (c) monitoring the frequency spectrum of the stress vibrations during therapy in order to determine if the kidney stone is fragmented, the monitoring comprising: comparing the frequency spectrum of the stress vibrations induced by the initial shock wave with the frequency spectrum of the stress vibrations induced by the at least one subsequent shock wave to detect a change in the frequency spectrum, the change in the frequency spectrum being indicative of fragmentation.