Presented by: Eduardo Gonzalez-Cuenca
Division of Urology, Department of Surgery, Schulich School of Medicine and Dentistry. Western University, London, ON, Canada.

Introduction

The Holmium:yttrium-aluminium-garnet (Ho:YAG) laser has become indispensable in endourology since its introduction in 1995, due to its wide safety margin and efficient stone fragmentation capabilities. Various technological advancements in laser lithotripsy have been developed since then, in an attempt to overcome some of the limitations of the original devices. The Thulium Fiber Laser (TFL), is the latest innovation and early clinical experience has suggested improvements in stone fragmentation and dusting capabilities compared to the Ho:YAG laser. The aim of our research was to compare the 2 laser technologies in a prospective, randomized protocol to investigate whether there were any differences in the efficiency of stone disruption including laser on time and total energy.  

Materials

Patients undergoing ureteroscopy for renal stones from a single institution were recruited and prospectively assigned to receive either the Ho:YAG or TFL laser for their procedure. Patients ­≥18-years-old with a renal calculi 8-20mm in size and a mean stone density of >600 Hounsfield units were included. Pre-operative patient and stone characteristics, intra-operative variables including laser time, energy and operative time were assessed. Post-operative outcomes including 3-month post-operative stone free rate on CT scan and complication rates were compared.  

Results

,

To date, 30 patients have been recruited (15 in each arm).  The laser-on time (p=.683), total operative time (p=.578), total laser energy (p=.935), ablation speed (p=.345) and ablation efficiency (p=.713) were not statistical different between groups. Trends in favor of TFL were seen in shorter laser-on time (384 VS 521 s), total operative (35.6 VS 38.2 min), decreased Total Laser Energy (6273 VS 6919 J), improved ablation efficiency (11.3 VS 11.9 J/mm³) and increased ablation speed (1.09 VS 1.19 mm³/second). To date, we have available 3-month follow-up information from 10 patients with post-operative non-constrast CT scan.

Conclusion

Preliminary results suggest similar outcomes between the two laser technologies for routine ureteroscopy in renal stone disease. However, several parameters are trending in favor of the TFL laser technology and recruitment fulfillment will be necessary to determine if there is significant difference between TFL and Ho:YAG laser technologies that are clinically meaningful.

Funding

No conflicts of interest from the authors

Lead Authors

Mario Basulto-Martinez,
Division of Urology, Department of Surgery, Schulich School of Medicine and Dentistry. Western University, London, ON, Canada.

Co-Authors

Linda Nott,
Division of Urology, Department of Surgery, Schulich School of Medicine and Dentistry. Western University, London, ON, Canada.

Stephen E. Pautler,
Division of Urology, Department of Surgery, Schulich School of Medicine and Dentistry. Western University, London, ON, Canada.

John Denstedt,
Division of Urology, Department of Surgery, Schulich School of Medicine and Dentistry. Western University, London, ON, Canada.

Jennifer Bjazevic,
Division of Urology, Department of Surgery, Schulich School of Medicine and Dentistry. Western University, London, ON, Canada.

Hassan Razvi,
Division of Urology, Department of Surgery, Schulich School of Medicine and Dentistry. Western University, London, ON, Canada.