A Novel Surgical Technique for Treatment of Renal Stones in Preschool-aged Patients: Initial Experience With Needle-perc

Objective: To describe and evaluate our newly developed minimal instrumentation technique, needle-perc, for treatment of preschool-aged patients with renal stones. To the best of our knowledge, this is the smallest endoscopic equipment for percutaneous nephrolithotomy reported thus far.

Materials And Methods: Needle-perc was performed in 8 patients using a 4.2-Fr needle to achieve access to the collecting system under ultrasonic guidance alone. The mean patient age was 2.4 years (range, 0-5 years). Five of the 8 patients were boys, while 3 were girls. Six patients had unilateral stones and 2 patients had bilateral stones. Six renal units exhibited single calculus, 2 exhibited staghorn stones, and 2 exhibited multiple stones. The mean calculus size was 1.6 cm (range, 0.8-4.5 cm). Preoperative, intraoperative, and postoperative parameters were analyzed prospectively.

Results: Access was successfully achieved in all patients. Puncturing was fully guided by ultrasound. Five patients underwent needle-perc alone. Two patients were transferred to 16-Fr access because of intrarenal infection and large stone burden. One patient underwent reduction of tract number. The mean operative time was 49.2 minutes (range, 22-75 minutes); mean hemoglobin loss was 5.2 g/L (range, 0-13.8 g/L). The mean postoperative hospital stay was 5 days (range, 3-7 days). Preplaced catheters were kept for 2-3 days to facilitate fragment discharge. Complications occurred in 2 patients: fever >38.5°C. The stone-free rate was 100% at 1 month postoperatively.

Conclusion: Our initial data indicate that needle-perc is feasible and safe for preschool-aged renal patients. Further studies are required to define its usefulness in treatment of larger stones.