Table 1.

Baseline characteristics of patients and stone

Mean age (years)	3.51±1.82 (4–168 months)
Male/female	74/26
Stone diameter (cm)	1.49±0.92 (0.5–3)
Lateralization (L/R/B)	42/39/19
Stone location
Renal pelvis	23
Upper pole calyx	11
Mid pole calyx	13
Lower pole calyx	28
Ureter	55
Symptom
Back pain	26
Hematuria	26
Fever	8
Symptomless	40

B: bilateral; L: left; R: right.