In Vitro Comparison of Dusting and Fragmentation Techniques Using Holmium: YAG Laser Lithotripsy: Efficacy and Thermal Impact Assessment

Abstract

Aim: Due to the potential risks of thermal effects during Ho:YAG laser lithotripsy, different techniques may vary in efficacy and safety. This study compares the stone fragmentation efficiency and temperature elevation associated with dusting and fragmentation techniques using the Ho:YAG laser in an experimental model.

Material and Methods: Using an artificial renal calyx model, ten experimental tubes and phantom stones were prepared for each technique. Energy settings were 0.5 J–20 Hz for the dusting technique and 1 J–10 Hz for the fragmentation technique. Temperature was measured every minute for five minutes, and stone weights were assessed.

Results: The fragmentation technique resulted in significantly greater stone mass reduction from the first minute onward (p < 0.001). Although the average temperature increase was higher in the dusting group, the intergroup difference was insignificant (p = 0.144). In both techniques, the thermal threshold of 43 °C was exceeded at the 2nd to 3rd minute.

Conclusion: The findings of this study underscore the importance of choosing a technique for Ho:YAG laser lithotripsy. The fragmentation technique was more effective for stone disintegration, while the dusting technique posed a higher thermal risk. The Ho:YAG laser method directly impacts clinical success and patient safety, highlighting the need for further research and careful consideration in clinical practice.

Keywords

• Ho:YAG laser
• retrograde intrarenal surgery
• dusting
• fragmentation
• thermal damage

Supporting Institution

This research was supported by the Scientific Research Projects Coordination Unit of Duzce University (Project No: 2019.04.02.1040).

Project Number

This study was supported by Düzce University BAP - DÜBAP 2019.04.02.1040 Scientific Research Project

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