1245 Ex-Vivo Comparison of Stone Clearance Rates Using Trilogy™ vs Thulium Fibre Laser (TFL) Lithotripsy

Introduction

There has been recent introduction of novel lithotripters and high-power lasers for stone disintegration. The latest in vitro and in vivo literature highlights the superiority of TFL vs standard Holmium:YAG (Ho:YAG) lithotripsy. This study aimed to evaluate the efficiency of Trilogy™ compared to TFL ex-vivo with regard to stone clearance rates.

Method

Kidney stone phantoms were made with BegoStone in 4 powder to water ratios of (15:3 to 15:6). The physical properties of these stone phantoms are comparable to kidney stones. The average clearance rate was calculated across a wide variety of settings (N = 27) for each of the 4 stone types with the Trilogy™ using size 34mm x 340mm probes. The settings of 1 Joule and 20 Hertz for a power of 20 Watts was used (N = 3) for the 4 different stone phantoms with the TFL using a size 500µm laser fibre utilised in percutaneous nephrolithotomy (PCNL).

Results

With the Trilogy™, calcium oxalate monohydrate (COM) (15:3) stone phantoms had an average stone clearance rate of 498.40 mm3/min, calcium phosphate (CaP) (15:4) had an average clearance rate of 493.60 mm3/min, uric acid (UA) (15:5) were cleared at a rate of 1267.61 mm3/min and struvite (15:6) cleared with a rate of 1299.64 mm3/min.

Using TFL, COM had an average clearance rate of 40.74 mm3/min, CaP were cleared at 39.65 mm3/min, UA at 39.5mm3/min and struvite were cleared at an average rate of 56.41 mm3/min.

Conclusions

The Trilogy™ had statistically significantly faster stone clearance rates across all 4 stone types (p = 0.03).