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Dependence of laser-induced tissue ablation on optical fiber movements for laser prostatectomy

  • Hyun Wook KangEmail author
  • Benjamin B. Choi
Original Article
  • 10 Downloads

Abstract

Purpose

The aim of the current study was to identify the efficient fiber movements for 532-nm laser prostatectomy.

Materials and methods

532-nm Lithium triborate (LBO) laser light was tested on 120 kidney tissues at three different translational speeds (TS 1, 2, and 4 mm/s) and four different rotational speeds (RS 0.5, 1.0, 1.6, and 2.1 rad/s). The applied power was 120 W at a 2-mm working distance and 60° sweeping angle. Ablation rate and dimensions of resulting ablation craters were measured.

Results

Slower TSs and RSs created deeper and wider ablation craters with thinner coagulation, leading to more efficient ablation performance. Maximal ablation rate was achieved at a TS of 2 mm/s and RSs of 0.5 and 1.0 rad/s. An RS of 0.5 rad/s accompanied surface carbonization for all the TSs. Irrespective of TS, ablation rate became saturated at faster RSs than 1.0 rad/s. Faster TSs or RSs reduced tissue ablation, but increased thermal coagulation due to a shorter interaction time.

Conclusions

Optimal ablation efficiency occurred at a TS of 2 mm/s and a RS of 1.0 rad/s with a thin coagulation of around 1.0 mm and no or minimal carbonization. Further studies will validate the current findings with prostate tissue and high-power levels for laser prostatectomy.

Keywords

Ablation Coagulation Laser prostatectomy Rotational speed Translational speed 

Notes

Acknowledgements

This work was supported by the Pukyong National University Research Fund in 2018.

Author contributions

HWK: research design, data collection, and manuscript writing; BBC: research design, data analysis, and manuscript writing.

Compliance with ethical standards

Conflict of interest

The authors declare that they have no conflict of interest.

Informed consent

Informed consent was obtained from all individual participants included in the study.

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Copyright information

© Springer-Verlag GmbH Germany, part of Springer Nature 2019

Authors and Affiliations

  1. 1.Department of Biomedical Engineering and Center for Marine-Integrated Biomedical Technology (BK21 Plus)Pukyong National UniversityBusanRepublic of Korea
  2. 2.Department of UrologyWeill Cornell MedicineNew YorkUSA

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