Extracorporeal shock wave lithotripsy for renal calculi.

PURPOSE

To gain better understanding of ESWL efficacy in children with renal calculi we report our outcomes using this technique.

MATERIALS AND METHODS

We reviewed the records of children who underwent ESWL as monotherapy for renal calculi at our institution from 1988 to 2007. Data included clinical characteristics, stone-free rate and its relationship to stone size and location, lithotriptor and complications.

RESULTS

The 33 boys and 29 girls with an average age of 10 years underwent a total of 69 treatments. A 53% and 63% stone-free rate was achieved after 1 and 2 ESWL sessions, respectively. A trend toward a higher stone-free rate (61% to 70%) after 1 ESWL session was seen in children with stones less than 50 mm(2), renal pelvic stones and treatment with the Dornier HM3 lithotriptor. Children with stones greater than 100 mm(2), a caliceal location and those treated with the Dornier MFL 5000 lithotriptor had a higher failure rate (25% to 46%). Five patients (8%) required ureteroscopy after ESWL due to retained distal ureteral stone fragments. Five patients (8%) who were not stone-free after therapy required subsequent endoscopic treatment for the stone during followup.

CONCLUSIONS

Smaller renal stones, renal pelvic calculi and treatment with an older generation lithotriptor were independent variables associated with a higher stone-free rate in children. While ESWL is a simple method in children with renal calculi, those with large or caliceal stones may do best with a primary endoscopic approach.