Safety of Thulium Fiber Laser Litothripsy in the Management of Large Renal Stones (>1000 mm³) and Factors Affecting Treatment Success

Safety of Thulium Fiber Laser Litothripsy in the Management of Large Renal Stones (>1000 mm³) and Factors Affecting Treatment Success:

The aim of this study is to compare the efficacy and safety of Thulium Fiber Laser (TFL) litothripsy according to stone density and the factors affecting success in patients undergoing retrograde intrarenal surgery (RIRS) for renal calculi >1000 mm3. Between November 2023 and December 2024, 81 patients with a stone volume >1000 mm3 who underwent RIRS with TFL in our clinic were prospectively and sequentially evaluated. Stone density of the patients was measured, and expressed in Hounsfield Units (HU). Patients with stone densities <1000 HU and ≥1000 HU were categorized as Groups 1, and 2, respectively. Demographic data, data of intraoperative laser use, stone-free rates (SFRs), the need for a second session of RIRS and complications were recorded. Duration of TFL litothripsy, total energy used, laser ablation speed (mm3/sec), laser ablation efficiency (mm3/J) and laser energy consumption (J/mm3) were calculated. Correlation tests, univariate and multivariate logistic regression tests were used for statistical analysis.

Inclusion Criteria:

• Patients ≥18 years of age
• Presence of kidney stones larger than 1000 mm³
• Patients with single or multiple kidney stones
• Patients eligible for retrograde intrarenal surgery (RIRS)

Exclusion Criteria:

• Patients younger than 18 years
• Pregnant or breastfeeding women
• Patients with uncorrected coagulopathy
• Patients with active urinary tract infection
• Patients with severe anatomic abnormalities preventing RIRS
• Patients unwilling or unable to provide informed consent