[Management of calyceal diverticular calculi with stenotic infundibulum by flexible ureteroscopic holmium laser infundibulectomy and lithotripsy].

Objective: To evaluate the efficacy and safety of flexible ureteroscopic holmium laser lithotripsy in treating calyceal diverticular calculi with stenotic infundibulum and to present our initial experience.

Methods: From Nov. 2012 to Nov. 2014, 10 patients with stone-bearing calyceal diverticulum and stenotic infundibulum underwent flexible ureteroscopic holmium laser lithotripsy in our hospital, including 3 female patients and 7 male patients with an average age of 36.9 years (range: 20 to 62 years). There were 6 patients with right side while 4 patients with left side calyceal diverticular calculi. The average cumulative stone size was (1.33±0.43) cm. Five patients underwent extracorporeal shock wave lithotripsy (ESWL) before hospital admission but no stone was discharged. All the patients received intravenous urography (IVU) and CT-urography (CTU) preoperatively and underwent double-J stents placement 2 weeks before operations. A digital-fiber flexible ureteroscopy and 200 μm holmium laser fiber were used for treatment. Surgeries began with routine flexible ureteroscopy and methylene blue injection was used to identify the small ostium of infundibulum. Then infundibulectomy followed by lithotripsy was performed. All the patients receive double-J stents placement and traditional Chinese medicine for 1 to 3 months after operations. The stone clearance was estimated by kidney ureter bladder (KUB) within 3 months' follow up.

Results: The locations of calyceal diverticulum were upper pole in 7 patients, and interpolar regions in 4 patients. The average operation time was (123.7±59.6) min, and the average estimated blood loss was (29.3±32.1) mL. Successful flexible ureteroscopic holmium laser infundibulectomies were performed in all the 10 patients. Success rate was 100%. The stone clearance rates for 1 and 3 months after surgery were 50.0% and 80.0%, respectively, which were observed by KUB follow-up. Two patients had serious post-operative fever (>38.0 °C) in coexistence with chills. The mobidity of urosepsis was 20.0%. No major complications were identified.

Conclusion: In selected patients, calyceal diverticular calculi with stenotic infundibulum can be treated safely and efficiently with flexible ureteroscopic homium laser lithotripsy. CTU and IVU should be completed preoperatively for calyceal diverticulum location and technique difficulty prediction. Retrograde methylene blue injection can be used to identify the ostium during surgery. And prolonged post-operation stone clearance was observed.