In search of optimal settings for Ho:YAG laser-lithotripsy to maximize the ablation rate, while minimizing the retropulsion

Author(s):  
Jian J. Zhang ◽  
Dongyul Chai ◽  
Jason R. Xuan ◽  
Aditi Ray ◽  
Thomas C. Hasenberg ◽  
...  
2014 ◽  
Vol 33 (4) ◽  
pp. 471-477 ◽  
Author(s):  
Markus J. Bader ◽  
Thomas Pongratz ◽  
Wael Khoder ◽  
Christian G. Stief ◽  
Thomas Herrmann ◽  
...  

2018 ◽  
Vol 2018 ◽  
pp. 1-11
Author(s):  
Jian J. Zhang ◽  
Jonathan Rutherford ◽  
Metasebya Solomon ◽  
Brian Cheng ◽  
Jason R. Xuan ◽  
...  

Objectives.Although laser lithotripsy is now the preferred treatment option for urolithiasis due to shorter operation time and a better stone-free rate, the optimal laser settings for URS (ureteroscopic lithotripsy) for less operation time remain unclear. The aim of this study was to look for quantitative responses of calculus ablation and retropulsion by performing operator-independent experiments to determine the best fit versus the pulse energy, pulse width, and the number of pulses.Methods.A lab-built Ho:YAG laser was used as the laser pulse source, with a pulse energy from 0.2 J up to 3.0 J and a pulse width of 150 μs up to 1000 μs. The retropulsion was monitored using a high-speed camera, and the laser-induced craters were evaluated with a 3-D digital microscope. The best fit to the experimental data is done by a design of experiment software.Results.The numerical formulas for the response surfaces of ablation speed and retropulsion amplitude are generated.Conclusions.The longer the pulse, the less the ablation or retropulsion, while the longer pulse makes the ablation decrease faster than the retropulsion. The best quadratic fit of the response surface for the volume of ablation varied nonlinearly with pulse duration and pulse number.


2017 ◽  
Author(s):  
Jian J. Zhang ◽  
Jonathan Rutherford ◽  
Metasebya Solomon ◽  
Brian Cheng ◽  
Jason R. Xuan ◽  
...  

2020 ◽  
Author(s):  
Yuan Cheng ◽  
Guangfa Wang ◽  
Wei Zhang ◽  
Hong Zhang ◽  
Xi Wang

Abstract Background: Treatment of broncholithiasis is complex, especially in the case of a large or transbronchial broncholith. Holmium-yttrium aluminum garnet (Ho:YAG) laser lithotripsy may be a useful treatment in broncholithiasis; however, as it is not yet common practice, the optimal parameters are unknown. Methods: We performed a single-center retrospective analysis of the clinical data of 13 broncholithiasis patients who underwent Ho:YAG laser lithotripsy from May 2012 to October 2018. Results: For the 13 patients (2 males and 11 females), Ho:YAG laser lithotripsy was performed 17 times, in total. All procedures were performed under general anesthesia with rigid bronchoscopy. We initially set the Ho:YAG laser to a pulse frequency of 5 Hz and a pulse energy of 0.8 J, gradually increasing these as required. The pulse frequency range we employed was 5-15 Hz, and the pulse energy range was 0.8-1.6 J. All broncholiths were successfully extracted after lithotripsy, and all symptoms improved. Hemoptysis, bronchial esophageal fistula, and pneumonia were the most common complications; however, there were no long-term complications. Conclusions: Ho:YAG laser lithotripsy is an effective and safe treatment for broncholithiasis, over a long-term follow up.


Urolithiasis ◽  
2019 ◽  
Vol 48 (3) ◽  
pp. 281-282 ◽  
Author(s):  
Takashi Kawahara ◽  
Kota Kobayashi ◽  
Shinnosuke Kurora ◽  
Masahiro Yao ◽  
Hiroji Uemura

Author(s):  
Jian J. Zhang ◽  
Dongyul Chai ◽  
Rongwei J. Xuan ◽  
Aditi Ray ◽  
Thomas Hasenberg ◽  
...  

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