Xenx (Xenolith): preliminary considerations of a new "all-in-one" ureteral guidewire and anti-repulsion device.

A new anti-retropulsion device for the endoscopic treatment of ureteral stones was evaluated for safety and potential efficacy. The Xenx™ (Rocamed, Monaco-Montecarlo) is an anti-retropulsion device that operates as a normal hydrophilic guidewire when "closed" and as a nitinol ureteral mesh when "open". We performed semirigid ureterorenoscopy and Ho:YAG Laser lithotripsy in 15 patients, with a single ureteral stone. For each procedure, the papilla was negotiated with the Xenx™, the radiopaque markers were positioned over the stone via direct visualization and the device was opened under fluoroscopic control. The ureteroscope was then retracted and reinserted beside the Xenx™. At the end of the procedure, the Xenx™ was closed, and a ureteral catheter was coaxially placed and left for 24-48 h post-operation. We evaluated device positioning success with respect to pushability, ease of deployment, full expansion and fitting with the ureteral walls, kink resistance and stone retention capabilities during lithotripsy and device retrieval. Operative time, post-operative complications (Clavien-Dindo scale), ultrasound kidney stone-free rate and the hydronephrosis grade, were also recorded. At 4 weeks post-operation, the stone-free rate was assessed via non-contrast computed tomography with 1-mm slices. All procedures were successfully accomplished without complications according to the Clavien-Dindo scale. In all the cases, Xenx™ was inserted successfully past the stone and opened over it. In 4/15 cases (27%) some difficulties in pushability and kink resistance were recorded. In no case stone fragment basketing was performed. The median operative time was 24 min. At hospital discharge, 14/15 patients (93%) were kidney stone-free. At 4 weeks, the NCCT stone-free rate was 100%. This study demonstrated that the Xenx™ is safe and effective in terms of the stone-free rate, complications and operating time. Moreover, use of the Xenx™ allows the use of a basket or guide wire to be avoided.