High frequency (HF) in laser lithotripsy lacks a consistent definition, potentially impacting clinical outcomes and patient safety. This review aims to analyze available evidence on the definition of HF.
A comprehensive literature search of MEDLINE, Scopus, and Cochrane databases identified English-language studies published up to November 2024. Those mentioning HF focused on Holmium:YAG (Ho:YAG), Thulium Fiber Laser (TFL), and pulsed Thulium:YAG (p-Tm:YAG) in ureteral and renal endoscopic procedures; in vitro experiments and reviews/editorials were also included. User manuals from high-power laser manufacturers, and data from artificial intelligence (AI) platforms were also analyzed.
From 1030 initial records, 857 studies were screened after duplicate removal, and 106 studies were ultimately included. Most articles came from Europe (46), followed by North America (37) and Asia (20). HF was poorly defined in 25 articles, distributed across Europe (11), North America (7), and Asia (7). Most studies evaluated Ho:YAG (N = 80), followed by TFL (N = 13) and p-Tm:YAG (N = 1); the rest evaluated the first two lasers or all three. HF definitions varied, with European studies reporting ranges from 10 to 200 Hz, North American studies from 10 to 120 Hz, and Asian studies from 10 to 200 Hz. On average, HF ranged from 40 to 50 Hz. Among manufacturers, only four out of eight provided HF definitions in pre-setting/starting guidelines. AI platforms defined HF as 15-100 Hz for Ho:YAG, 50-2000 Hz for TFL, and 20-500 Hz for p-Tm:YAG.
There is no consensus on HF definitions in laser lithotripsy, with limited manufacturer guidelines and overly broad AI-defined ranges. Standardized terminology is essential. We propose defining HF as > 30 Hz for renal and > 15 Hz for ureteral procedures. Based on the available evidence, the use of HF settings does not appear to be necessary for dusting or popcorning techniques with current technologies.
World journal of urology. 2025 May 08*** epublish ***
Alejandra Bravo-Balado, Stefano Moretto, Letizia Maria Ippolita Jannello, Alberto Quarà, Federico Zorzi, Stevee Doizi, Olivier Traxer, Frédéric Panthier
Endolase lab, GRC20, Sorbonne Université and PIMM-Arts et Métiers Paris Tech, Paris, France. ., Endolase lab, GRC20, Sorbonne Université and PIMM-Arts et Métiers Paris Tech, Paris, France.