[Determining factors in the success of the treatment of ureteral lithiasis by ESWL].

Shock-wave extracorporeal lithotripsy (SWEL) is admittedly the choice method for most ureteral calculi (UC). Treatment of 1.674 UC was carried out with a Lithostar (Siemens). Endourologic support manoeuvres (ESM) were used in 11.7% patients. To determine their statistical influence on treatment's result variables such as site, size, calculus density, obstruction and functionality of the renal unit, as well as presence of ureteral malformation, were analyzed. With an average of 1.3 sessions (9100 waves) success rate was 91.8% cases. Only the variables of size, obstruction and function showed statistical significance, thus identifying through a multistep logistic regression test the subgroup of calculi less likely to succeed (calculi > 1 cm2, with severe uropathy and functional annulment or delay). Complication were rare (7.5%) and minimally relevant. We conclude than SWEL is the first choice treatment for UC regardless the location. Ureteroscopy (UR) should be considered as the first option particularly in distal (iliopelvic ureter), obstructive calculi and those of difficult radiological study.