Objective To investigate the advantages of emergent ureteroscopy for the treatment of acute obstructive renal failure resulted from upper ureteral calculi.Methods A total of 123 cases of acute renal failure caused by bilateral upper ureteral calculi was treated with ureteroscopic exploration,ballistic lithotripsy,catheter indwelling,and percutaneous nephrolithotomy.Results The serum BUN(blood urea nitrogen) and Cr(creatinine) were decreased to normal levels 2～10 days after operation in 100 cases(81.3%);the levels of Cr were maintained at 188.6～232.3 ?mol/L 10～15 days after operation in 22 cases.In 1 case of congenital solitary kidney(renal failure caused by chronic contralateral ureteral calculous obstruction),a hemodialysis was needed on the 3rd day after operation,and the serum Cr was 810 ?mol/L on the 15th day after operation and was dropped to normal after 2 months postoperatively.In 4 cases of previous unilateral nephrectomy or congenital solitary kidney,azotaemia remained at 3 months after operation.Conclusions Emergent ureteroscopy for acute renal failure caused by calculous obstruction possesses advantages of immediate obstruction relief,effective renal function protection,little trauma,low complication rate,and simple performance.

Objective To discuss the efficacy of minimally invasive percutaneous nephrolithotomy(MPCNL) for residual or recurrent stones in the kidney or upper ureter after open surgery.Methods A total of 46 cases of residual or recurrent stones in the kidney or upper ureter after open surgery were included in the study.A pigtail catheter was inserted into the ureter transurethrally under ureteroscope to create an artificial hydronephrosis.Then a renal fistulization,usually on middle or upper calyx,was made.The stones were identified under ureteroscope,fragmented with a pneumatic ballistic lithotriptor,and extracted by using a grasping forceps.The renal fistulization tube was indwelled for drainage.Results The stones were completely removed on one session in 20 cases(43.4%),on two sessions in 15 cases(32.6%),and three in 8 cases(17.3%).Residual stones were seen in 3 cases(6.5%),with a size of 0.1 cm ? 0.1 cm ? 0.2 cm ～ 0.5 cm ? 0.5 cm ? 0.6 cm.Stones were removed through one working channel in 18 cases(39.1%),two channels in 20 cases(43.5%),and three channels in 8(17.4%).Conclusions The MPCNL is miuimally invasive and effective in the treatment of residual or recurrent stones after open surgery.