Removal of ureteral stones with extracorporeal shock wave lithotripsy and ureteroscopic procedures. What can we learn from the literature in terms of results and treatment efforts?

A literature review was made to obtain information on the treatment efforts required for a successful removal of ureteral stones when extracorporeal shock wave lithotripsy (ESWL) or ureteroscopic stone extraction or disintegration (URS) were used as primary procedures. Data were collected from 59 reports on ESWL and 23 on URS. The study thereby comprised 20,659 patients primarily treated with ESWL and 5,520 treated with URS. A treatment index (TI) was formulated from the total number of patients (N(TOT)), the number of stone free patients (N(SF)), the number of patients with retreatment (N(RE)), auxiliary procedures (N(AUX)) and general or regional anaesthesia (N(ANE)). The difference between the TI and the efficiency quotients normally used was the incorporation of the factor N(ANE) that reflected the need for general or regional anaesthesia. TI had the following form: TI = N(SF)/(N(TOT) + N(RE) + N(AUX) + N(ANE). When the groups of treated patients were considered in this way, TI was significantly higher for the patients treated with ESWL than for those treated with URS (P = 0.007). The median (range) for the groups of ESWL-treated patients was 0.50 (0.25-0.90) and for patients treated with URS 0.42 (0.26-0.94). For the combined groups of patients, the TI-values were 0.54 and 0.40, respectively. Although the average retreatment for URS was only 2.2% compared with 12.1 percent for ESWL, the need for general/regional anaesthesia was 94.3% and 28.3% in the two groups, respectively. The advantage of a lower rate of retreatment in patients primarily referred to URS was thus obviously counterbalanced by the much higher need for anaesthesia. For ureteral stones treated with ESWL in the author's department using Dornier HM3, MFL 5000, and Modulith SLX lithotripters, stone free rates of 96%, 97% an 95% were associated with TI-values of 0.61, 0.60 and 0.63, respectively. Both ESWL and URS are excellent procedures for the removal of stones from the ureter. In addition to the different degrees of invasiveness, the need for anaesthesia has to be considered in an objective comparison of the two methods.