Table 1.

Preoperative stone demographics.

Total stone number	173
Mean stone number	3.6 ± 3.0 (2–18)
Mean stone size (mm)	6.6 ± 3.6 (2–17)
Mean stone burden (mm)	22.2 ± 8.4 (12–45)
<20 mm (n = 23)	16.1 ± 2.4 (12–19)
≥20 mm (n = 25)	27.8 ± 8.1 (20–45)
Localization (n)
Upper calyx	21 (12.1%)
Middle calyx	42 (24.2%)
Lower calyx	69 (40.1%)
Renal pelvis	41 (23.6%)
Lateralization
Right side	23 (48%)
Left side	25 (52%)