Objectives: We investigated the relation between the presence and degree of stone induced hydronephrosis and the outcome of extracorporeal shock wave lithotripsy (SWL) in patients with solitary proximal ureteral stones.
Methods: 130 patients with or without hydronephrosis were treated with SWL. The degree of hydronephrosis was defined by renal ultrasound. Patients were divided into four groups according to the degree of stone induced hydronephrosis. Group 0 (24%) had no urinary system dilatation, group 1 (31.2%) had a mild dilatation of the renal pelvis, group 2 (40%) had a moderate and group 3 (4.8%) a severe dilatation of the renal pelvis and calices. The stone size, number of shock waves applied and number of sessions required to achieve stone clearance were recorded.
Results: Mean stone size was 8.2 mm+/-2.5 mm. Mean time to stone clearance was 13.7 days+/-16.3. In 74.4% of patients stone clearance was observed. Additional 4.8% harbored residual fragments < or =3 mm after 3 months. Differences among the four groups in terms of stone size, time to stone clearance and treatment failure were not significant.
Conclusions: The presence or degree of hydronephrosis caused by a proximal ureteral stone does not affect the time to stone clearance or success rate after SWL.