To explore the efficacy and safety of one-stage percutaneous nephrolithotomy combined with contralateral ureteral rigid/flexible endoscopy in oblique straddle position for bilateral upper urinary tract calculi.

Clinical data of patients with calculi in bilateral upper urinary tract undergoing one-stage surgery from May 2016 to September 2017 were retrospectively analyzed. The patients were kept in a 45° straddle position during percutaneous nephroscopy. Firstly, rigid/flexible ureteroscopy was performed on one side, and then percutaneous nephroscopy was conducted on the contralateral side. Blood routine examination was performed at postoperative 1 d, and kidneys-ureters-bladder (KUB) radiograph or ultrasound was performed at 1 month after operation.

Among 22 eligible patients, 21 patients successfully completed the surgery, and 1 patient terminated the operation due to unbearable chest pain during percutaneous nephroscopy. The preoperative stone size was measured as (28.9±6.1, 21.0-42.2) mm on the percutaneous nephroscopy side and (10.3±3.3, 6.0-17.0) mm on the rigid/flexible ureteroscopy side. The average operation time was (109±47, 45-225) min. The hemoglobin level was decreased by (1.8±1.6, 0-6.0) g/dL. The average length of hospital stay was (12±4, 7-21) d. No severe complications occurred during or after the surgery.

Oblique straddle position is an ideal position for one-stage surgery consisting of percutaneous nephroscopy on one side and rigid/flexible ureteroscopy on the contralateral side.