Related Experiment Videos
Shockwave frequency affects fragmentation in a kidney stone model
1Division of Urology, Saint Michael's Hospital and University of Toronto, Canada.
Journal of Endourology
|October 13, 2000
Summary
Higher shockwave frequencies require more shocks to fragment stones, impacting lithotripsy efficiency. Electrode pressure output remained consistent across tested frequencies, suggesting fragmentation differences are due to stone disintegration mechanisms, not electrode function.
Area of Science:
- Biomedical Engineering
- Medical Physics
- Urology
Background:
- Extracorporeal shock wave lithotripsy (ESWL) is a common procedure for kidney stone treatment.
- Optimizing ESWL parameters is crucial for improving stone fragmentation efficiency and reducing treatment time.
Purpose of the Study:
- To investigate the impact of varying shockwave frequencies on the efficiency of stone fragmentation using the MFL 5000 spark-gap lithotripter.
- To analyze the relationship between shockwave frequency, electrode consumption, and electrode pressure output during stone fragmentation.
Main Methods:
- Standardized plaster stones (12.0 +/- 0.5 mm) were fragmented at 20 kV energy.
- Shockwave frequencies tested included 60, 80, and 117 per minute.
- Fragmentation was performed throughout the electrode's lifespan (0 to >100% consumption), with electrode pressure output monitored at each frequency.
Main Results:
- A statistically significant increase in the number of shocks required for stone fragmentation was observed at higher frequencies (regression coefficient 1.93; p < 0.003).
- An inverse relationship was found between the number of shocks needed for fragmentation and electrode consumption (regression coefficient -2.16; p < 0.001).
- Electrode pressure output showed no linear correlation with either frequency (regression coefficient -0.40; p < 0.728) or electrode consumption (regression coefficient -1.11; p < 0.158).
Conclusions:
- Shockwave frequency significantly influences the number of shocks required for stone fragmentation.
- Increasing frequency from 60 to 117 shocks per minute notably increased the shocks needed to break stones.
- The consistent electrode pressure output across frequencies suggests that stone disintegration mechanisms, rather than electrode function, are primarily responsible for observed fragmentation differences.