Optimal Settings for the Noncontact Holmium:YAG Stone Fragmentation Popcorn Technique.

Title Optimal Settings for the Noncontact Holmium:YAG Stone Fragmentation Popcorn Technique.
Authors E. Emiliani; M. Talso; S.Y. Cho; M. Baghdadi; S. Mahmoud; H. Pinheiro; O. Traxer
Journal J Urol
DOI 10.1016/j.juro.2017.02.3371

PURPOSE: The purpose of this study was to evaluate the popcorn technique using a wide range of holmium laser settings and fiber sizes in a systematic in vitro assessment.

MATERIALS AND METHODS: Evaluations were done with 4 artificial stones in a collection tube. A fixed ureteroscope was inserted through a ureteral access sheath to provide constant irrigation flow and the laser was placed 1 mm from the bottom. Combinations of 0.5 to 1.5 J, 10 to 20 and 40 Hz, and long and short pulses were tested for 2 and 4 minutes. We used 273 and 365 ?m laser fibers. All tests were repeated 3 times. The stones were weighed before and after the experiments to evaluate the setting efficiency. Significant predictors of a highly efficient technique were assessed.

RESULTS: A total of 144 tests were performed. Mean starting weight of the stones was 0.23 gm, which was consistent among the groups. After the experiment the median weight difference was 0.07 gm (range 0.01 to 0.24). When designating a 50% reduction in stone volume as the threshold indicating high efficiency, the significant predictors of an efficient popcorn technique were a long pulse (OR 2.7, 95% CI 1.05-7.15), a longer duration (OR 11.4, 95% CI 3.88-33.29), a small (273 ?m) laser fiber (OR 0.23, 95% CI 0.08-0.70) and higher power (W) (OR 1.14, 95% CI 1.09-1.20).

CONCLUSIONS: Higher energy, a longer pulse, frequencies higher than 10 Hz, a longer duration and a smaller laser fiber predict a popcorn technique that is more efficient at reducing stone volume.

Citation E. Emiliani; M. Talso; S.Y. Cho; M. Baghdadi; S. Mahmoud; H. Pinheiro; O. Traxer.Optimal Settings for the Noncontact Holmium:YAG Stone Fragmentation Popcorn Technique.. J Urol. 2017;198(3):702706. doi:10.1016/j.juro.2017.02.3371

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See more Aluminum products. Aluminum (or Aluminium) (atomic symbol: Al, atomic number: 13) is a Block P, Group 13, Period 3 element with an atomic weight of 26.9815386. It is the third most abundant element in the earth's crust and the most abundant metallic element. Aluminum Bohr Model Aluminum's name is derived from alumina, the mineral from which Sir Humphrey Davy attempted to refine it from in 1812. Aluminum was first predicted by Antoine Lavoisier 1787 and first isolated by Hans Christian Øersted in 1825. Aluminum is a silvery gray metal that possesses many desirable characteristics. It is light, nonmagnetic and non-sparking. It stands second among metals in the scale of malleability, and sixth in ductility. It is extensively used in many industrial applications where a strong, light, easily constructed material is needed. Elemental AluminumAlthough it has only 60% of the electrical conductivity of copper, it is used in electrical transmission lines because of its light weight. Pure aluminum is soft and lacks strength, but alloyed with small amounts of copper, magnesium, silicon, manganese, or other elements, it imparts a variety of useful properties.


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