4 mm)in the kidney,and were then treated by ESWL combined with oral dissolution agents.The cure rate of this series was 97.7%(86/87).The patients were discharged from the hospital 4 to 16 days(mean,6.3 days)after the treatment.One patient developed massive hemorrhage and was then cured by selective embolization of the small renal vessels.86 patients were followed up for 3 to 18 months(mean,6.3 months),none of them had residual stones during this period.The symptoms of hydronephrosis was improved in all of the cases.Conclusions B-ultrasonography guided MPCNL with holmium:YAG laser is convenient,safe,and effective for upper urinary tract stone.

Objective To compare the efficacy and safety between rigid combined with flexible ureteroscopic lithotripsy and minimally invasive percutaneous nephrolithotomy ( MPCNL ) for impacted upper ureteral calculi . Methods We retrospectively analyzed 102 cases of impacted upper ureteral calculi treated in our hospital between June 2010 and April 2015.The patients were divided into two groups according to treatment methods: 54 cases underwent rigid combined with flexible ureteroscopic lithotripsy ( Combined group ) and 48 cases received MPCNL ( MPCNL group ) .The operation time , blood loss during operation , clearance rate of the stone, incidence of postoperative complications , and hospitalization time were statistically analyzed . Results All the patients tolerated operations without severe complications .The mean operation time of the Combined group was (87.9 ±21.6) min, which was significantly longer than that of the MPCNL group [(61.5 ±16.7) min, t=-6.795, P=0.000].The intraoperative blood loss in the MPCNL group was (52.8 ±9.6) ml, which was higher than that of the Combined group [(12.5 ±2.6) ml, t=29.644, P=0.000].The mean postoperative hospitalization time in the MPCNL group was (6.1 ±1.3) d, which was longer than that in the Combined group [(2.8 ±0.7) d, t=16.162, P=0.000].There was no significant difference in the incidence of postoperative complications between the two groups (χ2 =0.330, P=0.566).The stone clearance rates after one month postoperation were 95.7％(45/47) and 94.4％(51/54) in the MPCNL group and Combined group , but there was no signification difference between the two groups (χ2 =0.000, P=1.000). Conclusions Both rigid combined with flexible ureteroscopic lithotripsy and MPCNL are effective and safe for impacted upper ureteral calculi .Rigid combined with flexible ureteroscopic lithotripsy is a kind of natural orifice transluminal endoscopic surgery , which has no direct damage to the renal parenchyma with less bleeding and trauma , and shorter hospitalization time.