To evaluate the safety and clinical efficacy of modular flexible ureteroscopy combined with holmium laser lithotripsy in the treatment of upper urinary tract calculi.

Clinical data of 433 patients diagnosed with the upper urinary tract calculi treated with flexible ureteroscopy in our hospital from April 2015 to April 2017 were collected. Among them, 178 cases were diagnosed with solitary calculi and 255 cases of multiple calculi. The calculi were observed in the middle and upper calyces of kidney of 132 patients, the lower calyces of kidney of 97 cases and the upper ureter and renal pelvis of 204 patients. The diameter of the calculi was ranged from 0.8 to 4.0 cm.

The success rate of one-time ureteroscope placement was 100%. The operation time was 30-280 min. The length of postoperative hospital stay was 1.0-5.0 d. The calculi were not detected in one patient and then extracorporeal shock wave lithotripsy was adopted. Three cases were treated with percutaneous nephrolithotomy because the optical fiber failed to detect the stones. The remaining 429 patients underwent modular flexible ureteroscopy. At postoperative two weeks, plain abdominal or urinary CT scan demonstrated that the stone removal rate was 84.4% (362/429). Secondary operation was performed in 37 cases. The final stone removal rate was 89.9% (386/429). No severe postoperative complications, such as ureteral perforation, avulsion and massive bleeding, occurred.

The modular flexible ureteroscopy combined with holmium laser is safe and effective treatment of the upper urinary tract calculi, which serves as an ideal therapeutic option for the upper urinary tract and renal calculi in clinical practice.