# Comparative Analysis of the Thulium Fiber Laser, Holmium: YAG Laser, and Pneumatic Lithotripter in Mini-Percutaneous Nephrolithotomy: A Tertiary Care Center Experience

## TL;DR

This study compares three tools used in kidney stone surgery, finding that the thulium fiber laser is faster and more efficient but may have long-term risks.

## Contribution

The study provides direct comparative evidence on the performance of TFL, Holmium: YAG, and pneumatic lithotripters in mini-PCNL.

## Key findings

- TFL had significantly shorter stone disintegration and operative times compared to other methods.
- TFL achieved the highest stone-free rate and used less energy per case.
- TFL showed lower blood loss but a potential trend toward higher long-term stenosis.

## Abstract

Background

Mini-percutaneous nephrolithotomy (mini-PCNL) has become a standard treatment for moderate-sized renal calculi. Among intracorporeal lithotripters, the thulium fiber laser (TFL), Holmium: YAG laser, and pneumatic devices remain the most widely used, yet direct comparative evidence in mini-PCNL remains limited.

Aim

The aim of this study is to compare the intraoperative efficiency, perioperative outcomes, and long-term sequelae of TFL, Holmium: YAG, and pneumatic lithotripters in mini-PCNL.

Materials and methods

A comparative study was conducted in 221 patients undergoing mini-PCNL for 10-30 mm renal stones. Patients were allocated to TFL (n=79), Holmium: YAG (n=72), or pneumatic lithotripter (n=70) groups. Demographics, stone characteristics, intraoperative parameters, perioperative complications, and 12-month outcomes were analyzed. Statistical comparisons included ANOVA and chi-square tests, with significance set at p<0.05.

Results

Baseline characteristics were comparable across groups. Stone disintegration time was significantly shorter in the TFL group (24.17 ± 4.7 min) than Holmium (31.45 ± 6.3) and pneumatic groups (35.26 ± 5.9) (p<0.01). Mean operative time was lowest with TFL (53 ± 9.8 min) versus Holmium (71 ± 14.6) and pneumatic (83 ± 12.8) (p<0.001) groups. In laser groups, energy usage per case was markedly lower with TFL (15.95 kJ) compared to Holmium (23.59 kJ) (p<0.01). Stone-free rate (SFR) was highest with TFL (94.8%), followed by Holmium (84%) and pneumatic (79%) (p=0.02) groups. TFL also showed the lowest hemoglobin drop (0.44 g/dL) and hematocrit change (3.2%, both p<0.05). Complication rates by Clavien-Dindo classification were similar, though hematuria and sepsis were more frequent in the pneumatic group. At 12 months, infundibular stenosis was detected in six TFL, four Holmium, and two pneumatic patients (p=0.18). Kaplan-Meier analysis demonstrated a nonsignificant trend toward higher stenosis with TFL.

Conclusion

TFL offers superior intraoperative efficiency, reduced energy usage, and a higher SFR in mini-PCNL. However, the potential for increased long-term stenosis requires further evaluation. Clinicians should weigh immediate benefits against possible delayed sequelae when selecting the lithotripter modality.