What happened to shockwave lithotripsy during the past 22 years? A single-center experience

Introduction: From 1985 to August 2007 we have performed 15,324 shockwave lithotripsy (SWL) treatments using the Dornier HM3 lithotripter. We studied trends in the characteristics of treatments and patients. Patients and Methods: Patient data were recorded in a computerized database. Changes in characteristics of patients and stones treated during this period were reviewed. Results: A total of 15,324 treatments were performed on 10,734 patients. The following trends were observed: (1) Stone size: A significant increase in the proportion of patients treated for stones up to 10mm in diameter, no change for stone size of 10 to 20mm, and a decrease in stones larger than 20mm in diameter. (2) Stone location: A significant increase in the proportion of patients treated for proximal and distal ureteral calculi, whereas a significant decrease in those with renal pelvic and staghorn stones. (3) Auxiliary procedures: A significant increase in the use of perioperative procedures (stents or ureteral catheters) ranging from 20% during the mid-1980s up to 60% in the year 2007. (4) Presenting symptoms: A significant increase in the percentage of patients referred with pain and a significant decrease in the percentage of patients referred with signs of infection. (5) Repeat SWL: A total of 13% of the patients required a second SWL for the same stone within 90 days of the first procedure. (6) Complication rate: This rate was relatively low, ranging from 1% to 6% per year. Conclusions: The evolvement of endourological procedures and techniques resulted in a decreased referral of large kidney stones for SWL. Advanced diagnostic modalities increased the diagnosis of renal colic in patients presenting with pain, and consequently their referral rate and timing for SWL treatment. The use of stents increased because of referral of patients with obstructing stones and infection or for prevention of posttreatment obstruction.