Inclusion Criteria:  A single radiopaque kidney stone (5-20 mm) in diameter visible on CT scan of the abdomen.  Exclusion Criteria:  A lower calyx stone. A history of spontaneous stone passage. A previous failed ESWL. Treatment with alpha adrenergic antagonists, calcium channel inhibitors or steroids. Severe obesity (BMI≥40). Pregnancy. Serum creatinine ≥2 mg/dl. Renal artery aneurysm and/or abdominal aorta aneurysm. The presence of a ureteral stent. Anatomical abnormalities or previous surgery on the upper urinary tract. Bone deformities. Presence of a urinary tract infection. Coagulation disorders. Poorly controlled hypertension.