A Novel Technique of Ultra-Mini-Percutaneous Nephrolithotomy: Introduction and an Initial Experience for Treatment of Upper Urinary Calculi Less Than 2 cm

Table 2

Intraoperative and postoperative parameters.

Immediate stone-free rate (after 1 day)	88.9% (32/36)
Total stone-free rate (after 1 month)	97.2% (35/36)
Hospital stay (day)	3.0 ± 0.9 (2–5)
No. Double-J stent (%)	4 (11.1%)
Operative time (min)	59.8 ± 15.9 (30–90)
Hemoglobin drop (g/L)	5.4 ± 7.8 (0–21)
Second-look UMP	1 (2.8%)
No. of tract size 13Fr/11Fr	31 (86.1%)/5 (13.9%)
No. of puncture locations
Upper/middle/lower pole calyces	7 (19.4%)/15 (41.7%)/; 14 (38.9%)
Supracostal/infracostal	15 (41.7%)/21 (58.3%)
Posterior/anterior calyx	30 (83.3%)/6 (16.7%)
Significant complication	6 (16.7%)
Urosepsis	2 (5.6%)
Urinary extravasations	1 (2.8%)
Fever (>38.5°C)	3 (8.3%)
Stone analysis
Calcium oxalate and/or phosphate	18 (50%)
Struvite	1 (2.8%)
Uric acid	4 (11.1%)
Mix stones	13 (36.1%)