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
Abstract

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

Related Elements

Holmium

See more Holmium products. Holmium (atomic symbol: Ho, atomic number: 67) is a Block F, Group 3, Period 6 element with an atomic radius of 164.93032. Holmium Bohr ModelThe number of electrons in each of Holmium's shells is [2, 8, 18, 29, 8, 2] and its electron configuration is [Xe] 4f11 6s2. Elemental Holmium PictureThe holmium atom has a radius of 176 pm and its Covalent radius is 192±7 pm. Holmium was first discovered by Marc Delafontaine in 1878. In its elemental form, holmium has a silvery white appearance. It is relatively soft and malleable. It is stable in dry air at room temperature but rapidly oxidizes at elevated temperatures and in moist air. Holmium has unusual magnetic properties. Its name is derived from the Latin word Holmia meaning Stockholm.

Aluminum

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.

Yttrium

See more Yttrium products. Yttrium (atomic symbol: Y, atomic number: 39) is a Block D, Group 3, Period 5 element with an atomic weight of 88.90585. Yttrium Bohr ModelThe number of electrons in each of yttrium's shells is [2, 8, 18, 9, 2] and its electron configuration is [Kr] 4d1 5s2. The yttrium atom has a radius of 180 pm and a Van der Waals radius of 219 pm. Yttrium was discovered by Johann Gadolin in 1794 and first isolated by Carl Gustav Mosander in 1840. In its elemental form, Yttrium has a silvery white metallic appearance. Yttrium has the highest thermodynamic affinity for oxygen of any element. Elemental YttriumYttrium is not found in nature as a free element and is almost always found combined with the lanthanides in rare earth minerals. While not part of the rare earth series, it resembles the heavy rare earths which are sometimes referred to as the "yttrics" for this reason. Another unique characteristic derives from its ability to form crystals with useful properties. The name yttrium originated from a Swedish village near Vaxholm called Yttbery where it was discovered.

Related Forms & Applications