Ultra-mini percutaneous nephrolithotomy for the treatment of renal or upper ureteral stones (report of 32 cases)

Abstract

Objective To investigate the efficacy and safety of ultra-mini percutaneous nephrolithotomy for the treatment of renal or upper ureteral stones. Methods The data of 32 patients diagnosed as renal or upper ureteral stones were retrospectively reviewed, who underwent ultra-mini percutaneous nephrolithotomy from June to October, 2015, including 29 kidney stones, 3 upper ureteral stones, of which 21 single stone, 7 multiple stones, and 4 staghorn stones.There were 8 cases with inferior calyx stones , 10 with renal pelvis stones, 3 with upper ureteral stones, 10 with renal pelvis stones plus inferior calyx stones and 1 with renal pelvis stones plus upper calyx stones.The mean stone size was (20.1±7.6) mm (ranging from 10 to 41mm). The mean Hounsfield unit (HU) was (1 125.9±225.9 ) Hu (ranging from 520 to 1 550Hu). In this cohort, 13 cases had mild hydronephrosis, 2 moderate hydronephrosis, 1 severe hydronephrosis while no hydronephrosis identified in the other 16 patients. One case had concomitant kidney and ureter duplication malformation, and 1 case had residual stones after laparoscopic nephrolithotomy. Results All of the patients were treated by single tract UMP. Among them, middle calyceal puncture was performed in 9 cases, and the other 23 cases underwent lower calyceal puncture, including 4 cases of intercostal puncture, and 28 subcostal puncture. The mean operating time was(30.3±15.0)min (ranging from 10 to 90 min). The mean postoperative hospital stay was (1.9±1.0) days (ranging from 1 to 5 days). The mean hemoglobin decrease was(14.6±8.4)g/L (ranging from 1 to 46 g/L). No analgesics were used. Peri-operative complication rate was 3.13% (1/32) with 1 case of collection system perforation. There was no fever, severe bleeding, urinary extravasation, pleural injury, or blood transfusion. The SFR was 93.75% (30/32) and 96.88% (31/32) on the first day and the first month after the operation, respectively. Conclusions UMP could be a safe and effective method for the treatment of renal or upper ureteral stones, especially for inferior calyceal stones less than 2cm. It offers high stone clearance rate, minimally invasiveness, quick recovery, short length of hospital stay and improved quality of life. Key words: Kidney stone; Upper ureteral stone; Ultra-mini percutaneous nephrolithotomy; Percutaneous nephrolithotomy