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Load-release points of two novel ureteral stone-trapping devices
Michael K Ouwenga1, Sameer K Sharma, Paulette Holley
1Department of Urology, Loyola University Medical Center, Maywood, Illinois 60153, USA.
Journal of Endourology
|September 30, 2005
Summary
Both the Stone Cone and Cook Urological NTrap devices reliably released ureteral stones in vitro. The NTrap required more force, but both released stones at low loads, suggesting minimal risk of ureteral trauma.
Area of Science:
- Urology
- Biomedical Engineering
Background:
- Ureteral stones pose a significant clinical challenge.
- Effective retrieval devices are crucial for managing ureteral calculi.
- The Stone Cone and Cook Urological NTrap are designed for stone retrieval.
Purpose of the Study:
- To compare the load-release characteristics of the Stone Cone and Cook Urological NTrap devices.
- To evaluate device performance in an in vitro ureteral model.
Main Methods:
- An in vitro strictured ureter model was established using urethane tubing.
- A plastic bead simulated a ureteral stone.
- The force required for Stone Cone and NTrap deployment and release was measured over five trials.
Main Results:
- Both devices successfully released the simulated stone in all trials.
- The Stone Cone demonstrated a mean release load of 0.190 lb.
- The NTrap exhibited a mean release load of 0.861 lb, significantly higher than the Stone Cone.
Conclusions:
- Both Stone Cone and NTrap devices reliably release stones at low forces (<1 lb).
- The NTrap requires significantly more force for release compared to the Stone Cone.
- Further clinical trials are needed to determine if design differences impact stone-clearing efficacy.
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