Optimization of the sound fields for lithotripsy
Shock waves are used clinically since the 1980’s for the non-invasive fragmentation of kidney stones. For this purpose acoustic pulses with pressures of up to 150MPa and rise times in the nanosecond range are generated and focused on the stone inside the patient's body by suitable reflectors or surface geometries of the acoustic source. The kidney stone is then gradually fragmented by the mechanical stress of the shock waves and can leave the body with the urine.
Despite many years of experience, both doctors and manufacturers could so far not determine which shock wave and sound field shape is optimal for which phase of lithotripsy treatment. To investigate this relationship more precisely and to optimize a piezoelectric lithotripter, we develop concepts and measurement setups concerning the entire chain of action of stone disintegration depending on the sound field.
This includes:
- automated 3D sound field measurements with a fiber optic hydrophone
- determination of fragmentation of stones due to various sound fields by FEM simulations
- construction of an in-vitro evaluation environment for stone fragmentation
- development of new sound fields and investigation of their effect on stone fragmentation
Publications
- N. Reinhardt, J. Hahn, C. Bach, K. Radermacher & M. de la Fuente: Evaluation of Different In-Vitro Setups Concerning Transferability into Clinical Application of Extracorporeal Shockwave Lithotripsy. Abstract Book: International Symposium of ISTU, 5th European Symposium of EUFUS, 2019, pp. 287
- N. Reinhardt, K. Dietz-Laursonn, M. Janzen, C. Bach, K. Radermacher & M. de la Fuente: Experimental setup for evaluation of cavitation effects in ESWL. Current Directions in Biomedical Engineering, 2018, 4(1), pp. 191-194 [DOI: 10.1515/cdbme-2018-0047]