Use of NTrap during ureteroscopic Holmium:YAG laser lithotripsy of upper ureteral calculi

We investigated the effectiveness of NTrap in prevention of stone retropulsion during ureteroscopic Ho:YAG laser lithotripsy of upper ureteral calculi. A total of 308 patients with upper ureteral stones treated by semirigid ureteroscopic Ho: YAG laser were stratified into two groups in which 152 patients without NTrap use were assigned to Group I and 156 patients with NTrap use were assigned to Group II. Patient gender, age, stone size, operative time, and parameters for stone migration were compared between the two groups. The difference in patient gender, age, and stone size were insignificant between the two groups. Longer operative duration (P = 0.000) was observed in Group II. Group II showed a higher intraoperative success rate of lithotripsy (P = 0.000) and a lower postoperative stone residual rate (P = 0.070) compared with Group I. The overall success rate was higher in Group II (P = 0.000). NTrap is an effective occlusive device against upper ureteral calculi retropulsion during ureteroscopic Ho: YAG laser lithotripsy.