Rapid extracorporeal shock wave lithotripsy treatment after a first colic episode correlates with accelerated ureteral stone clearance

OBJECTIVES: To investigate the relationship between delay in extracorporeal shock wave lithotripsy (ESWL) after a first colic and subsequent time to complete stone clearance. METHODS: This prospective, non-randomized study included 94 patients treated with ESWL for unilateral solitary proximal ureteral stones after at least one episode of colic pain. Time between the first onset of colic pain and ESWL and stone clearance was recorded. The pretherapeutic degree of hydronephrosis has been assessed using ultrasound. RESULTS: Mean stone size was 7.9 +/- 2.3 mm and mean time before ESWL after a first colic was 93.4 +/- 143.5 h. At 3 months, 3 patients were lost to follow-up. In 76.9% of patients stones were completely cleared and a further 3.3% harbored residual fragments < or =3 mm. Delay in treatment after a first colic correlated with subsequent time to stone clearance (p < 0.0001). Mean time to stone clearance in patients treated within 24h was 6.4 +/- 6.3 days compared with 16.0 +/- 17.8 days for those treated later (p = 0.008). Maximum stone diameter correlated with time to stone clearance (p = 0.031), but the degree of hydronephrosis did not. CONCLUSIONS: Rapid ESWL after a first onset of colic pain resulted in accelerated stone clearance independent of the degree of hydronephrosis but had no impact on the need for auxiliary procedures.