Microperc versus miniperc for the management of medium‑sized renal stones: a comparative two‑center clinical study

Objective To date, there is very little evidence directly comparing the outcomes between Mini‑percutaneous nephrolithotomy and Micro‑percutaneous nephrolithotomy. Because of this evidence gap, we wanted to compare miniperc and microperc with an ultimate purpose to determine which modality is preferred for different stone characteristics. Our hope is that these findings may help guide which technique is most suitable for a given renal stone burden. Patients and methods This is a retrospective collaborative multi‑institutional study between Dortmund Teaching Hospital (Germany) and Modena University Hospital (Italy) in which we compared two matched groups of patients. The first group (32 patients) underwent miniperc for medium‑sized renal stones in Dortmund, and the second group (19 patients) underwent microperc in Modena. Both groups were matched according to age, sex, BMI, and maximum stone diameter according to preoperative plain KUB films. Results The primary stone‑free rates in the miniperc and microperc groups were similar (93.8 vs. 84.2%, P = 0.262). Mean operative time for miniperc was significantly shorter than that of microperc (45.6 ± 18.9 vs. 68.7 ± 35.2 min, P = 0.004). The overall complication rate was 11.7%, with no significant difference between the two groups (12.5% for miniperc vs. 10.5% for microperc, P = 0.604). Mean hospital stay in miniperc was significantly longer than that of microperc (4.7 ± 1.6 vs. 3 ± 1.5 days, P 0.001). Conclusion Our current data show that microperc is emerging as an effective and safe treatment option for intermediate‑sized kidney stones, with outcomes comparable even to miniperc, which is already a well‑established treatment with high safety profile in experienced hands.