Laser Ablation Efficiency, Laser Ablation Speed, and Laser Energy Consumption During Lithotripsy: What Are They and How Are They Defined? A Systematic Review and Proposal for a Standardized Terminology.

Laser performance for lithotripsy is currently reported using units of measurement such as J/mm3, mm3/J, mm3/s, s/mm3, and mm3/min. However, there are no current standardized definitions or terminology for these metrics.

This may lead to confusion when assessing and comparing different laser systems.

The primary objective was to summarize outcome values and corresponding terminology from studies on laser lithotripsy performance using stone volume in relation to time or energy. The secondary objective was to propose a standardized terminology for reporting laser performance metrics.

A systematic review of the literature was conducted using the search string ("j*/mm3" OR "mm3/j*" OR "mm3/s*" OR "s*/mm3" OR "mm3/min*" OR "min*/mm3" AND "lithotripsy") on Scopus, Web of Science, Embase, and PubMed databases. Study selection, data extraction, and quality assessment were performed independently by two authors.

A total of 28 studies were included, covering holmium:yttrium-aluminum-garnet (Ho:YAG), MOSES, and thulium fiber laser (TFL) technologies. Laser energy consumption values reported for the studies ranged from 2.0 - 43.5 J/mm3in vitro and from 2.7 - 47.8 J/mm3in vivo, translating to laser ablation efficiency of 0.023 - 0.500 mm3/J and 0.021 - 0.370 mm3/J, respectively. Laser ablation speeds ranged from 0.3 - 8.5 mm3/s in vivo, translating to lasing time consumption of 0.12 - 3.33 s/mm3. Laser efficacy ranged from 4.35 - 51.7 mm3/min in vivo. There was high heterogeneity for the terminology used to describe laser performance for the same metrics.

The range of laser performance metric values relating stone volume to energy or time is wide, with corresponding differing terminology. We propose a standardized terminology for future studies on laser lithotripsy, including laser ablation efficiency (mm3/J), laser ablation speed (mm3/s), and laser energy consumption (J/mm3). Laser efficacy (mm3/min) is proposed as a broader term that is based on the total operative time, encompassing the whole technique using the laser.

We reviewed studies to identify the units and terms used for laser performance when treating urinary stones. The review revealed a wide range of differing units, outcomes, and terms. Therefore, we propose a standardized terminology for future studies on laser stone treatment.

European urology focus. 2023 Nov 06 [Epub ahead of print]

Jia-Lun Kwok, Vincent De Coninck, Eugenio Ventimiglia, Frédéric Panthier, Mariela Corrales, Alba Sierra, Esteban Emiliani, Michele Talso, Arkadiusz Miernik, Peter Kronenberg, Dmitry Enikeev, Bhaskar Somani, Khurshid R Ghani, Olivier Traxer, Etienne Xavier Keller

Department of Urology, University Hospital Zurich, University of Zurich, Zurich, Switzerland; Department of Urology, Tan Tock Seng Hospital, Singapore, Singapore., Progressive Endourological Association for Research and Leading Solutions (PEARLS), Paris, France; Young Academic Urologists (YAU) Endourology and Urolithiasis Working Group, Arnhem, The Netherlands; Department of Urology, AZ Klina, Brasschaat, Belgium., Progressive Endourological Association for Research and Leading Solutions (PEARLS), Paris, France; Young Academic Urologists (YAU) Endourology and Urolithiasis Working Group, Arnhem, The Netherlands; Division of Experimental Oncology/Unit of Urology, Urological Research Institute, IRCCS Ospedale San Raffaele, Milan, Italy., Progressive Endourological Association for Research and Leading Solutions (PEARLS), Paris, France; Sorbonne Université, GRC n°20, Groupe de Recherche Clinique sur la Lithiase Urinaire, Hôpital Tenon, F-75020 Paris, France., Progressive Endourological Association for Research and Leading Solutions (PEARLS), Paris, France; Young Academic Urologists (YAU) Endourology and Urolithiasis Working Group, Arnhem, The Netherlands; Urology Department, Hospital Clinic de Barcelona, Barcelona, Spain., Young Academic Urologists (YAU) Endourology and Urolithiasis Working Group, Arnhem, The Netherlands; Department of Urology, Fundación Puigvert. Autonomous University of Barcelona, Barcelona, Spain; Progress in Endourology, Technology and Research Association (PETRA), Paris, France., Young Academic Urologists (YAU) Endourology and Urolithiasis Working Group, Arnhem, The Netherlands; Progress in Endourology, Technology and Research Association (PETRA), Paris, France; Department of Urology, ASST Fatebenefratelli-Sacco, Luigi Sacco University Hospital, Milan, Italy., Department of Urology, Faculty of Medicine, Medical Center, University of Freiburg, Freiburg, Germany., Progress in Endourology, Technology and Research Association (PETRA), Paris, France; Department of Urology, Hospital CUF Descobertas, Lisbon, Portugal., Department of Urology, Comprehensive Cancer Center, Medical University of Vienna, Vienna, Austria; Institute for Urology and Reproductive Health, Sechenov University, Moscow, Russia., Progress in Endourology, Technology and Research Association (PETRA), Paris, France; Department of Urology, University Hospital Southampton, Southampton, UK., Department of Urology, University of Michigan, Ann Arbor, MI, USA., Progressive Endourological Association for Research and Leading Solutions (PEARLS), Paris, France; Sorbonne Université, GRC n°20, Groupe de Recherche Clinique sur la Lithiase Urinaire, Hôpital Tenon, F-75020 Paris, France; Progress in Endourology, Technology and Research Association (PETRA), Paris, France., Department of Urology, University Hospital Zurich, University of Zurich, Zurich, Switzerland; Progressive Endourological Association for Research and Leading Solutions (PEARLS), Paris, France; Young Academic Urologists (YAU) Endourology and Urolithiasis Working Group, Arnhem, The Netherlands. Electronic address: .

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