One-Year Follow-Up of Unselected Group of Renal Stone Formers Treated with Extracorporeal Shock Wave Lithotripsy

Except in eight patients with very large staghorn stones, extracorporeal shock wave lithotripsy (ESWL) was used as primary treatment of 274 renal units in 250 patients. Because all patients were from our own county, where no percutaneous surgery was performed at the referring hospitals, the group was considered to represent an average profile of stone formers requiring surgery. The concrement size ranged from 2 mm to complete staghorn stones, and the results were analyzed in relation to ESWL types. The follow-up rate after 4 weeks was 100%, after 6 months 97%, and after 12 months 93%. In the whole group, 68% of the patients were stone-free after 6 months and 83% after 12 months. The patients who were stone free after 1 year had not been given more ESWL sessions or a higher energy than those who had residual fragments. The best results were recorded for ESWL types A, B, and F, whereas residual fragments were observed more commonly for ESWL types C, D, and E. Residual fragments were frequently found in patients with struvite and pure calcium phosphate stones. Most residual fragments were located in the lower caliceal system irrespective of the original location. The frequency of residual fragments increased with increasing number of stones in the kidney. A slower rate of fragment passage was observed in renal units with anatomic abnormalities or previous surgery. Auxiliary procedures were frequently required, but open or percutaneous surgery was necessary in only 13 patients, eight before and five after ESWL. Ureteral catheters were required in 70 (26%) and percutaneous nephrostomies in 21 (8%) of the renal units.