Treatment of ureteral stones with LithoEVO device and Vapor Tunnel tool

Vapor Tunnel (VT) technology is the result of a pulse modulation during holmium laser emission which reduces stone retropulsion. We present the outcomes of this tool in the treatment of ureteral stones.

Two hundred ten patients with a ureteral stone were randomly assigned to holmium laser lithotripsy with (group A) or without (group B) the VT technology. The 35 W LithoEVO laser generator (Quanta System, Samarate, Varese, Italy) was used. We compared operative time, dusting time, delivered energy, retreatment rate due to stone push-up, ureteral lesions, and stone-free rate (SFR) and postoperative strictures at 1 month. We also compared outcomes according to stone position.

VT technology was associated with significantly lower mean operative time (25.7 vs. 37.2 min), dusting time (9.7 vs. 15.3 min), delivered energy (7.7 vs. 19.9 KJ). In group B 9 patients (8.5%) were retreated due to stone push-up (P=0.01) for a proximal or middle stone, 6 (5.7%) postoperative strictures occurred (P=0.03) and a higher ureteral lesion rate was observed (7.6% vs 35.2%, P=0.04). 1-month SFR was comparable (93.4% vs. 88.6%, P=0.11). Postoperative complication rate was higher in group B (P=0.05). Without VT technology, ureteral lesions and strictures rates were significantly higher independently from stone position.

The VT technology is associated with significantly lower operative and dusting time independently from stone position, due to a reduced retropulsion, which makes treatment quicker and easier. It also avoids stone push-up especially for proximal and middle stones and reduces ureteral lesions, postoperative complications, and ureteral strictures.