Materials and methods: All patients admitted to Department of Urology A and B of Bind Dan hospital for holmium laser ureteroscopic lithotripsy from April 2011 to May 2012 with the following profile: Stone site: mid and distal ureteral stones, Stone size ≤ 15 mm, Stone unique, Mild to moderate hydronephrosis on ultrasound and / or KUB/CT.