RIRS vs PCNL in treating lower-pole renal stones: a comparative clinical outcome study

The reduced-pole renal stones with a length of 1-2 cal have a special anatomical problem, which could also influence the degree of efficacy of treatment and incidence rates. Retrograde intrarenal surgery (RIRS) and percutaneous nephrolithotomy (PCNL) are the two popular techniques of their treatment but the best method is yet questionable. The purpose of the research was to compare the perioperative outcome, complication profile, and stone-free rates between RIRS and PCNL as the forms of treatment of the lower-pole renal stones.

This study was designed as a retrospective multicenter comparative clinical outcome study. There was a total 177 adult patient, 1-2 cm solitary lower pole renal stones, 85 patients undergoing RIRS and 92 patients undergoing PCNL. The preoperative characteristics of the stones and anatomical parameters were estimated by non-contrast computed tomography. The intraoperative variables and the postoperative recovery outcomes and complications are noted. At 3 months, non-contrast CT was checked to identify if the patient was stone-free or not. The determination of complications was done using the Clavien-Dindo system. The parametric and nonparametric tests were conducted to perform a statistical comparison of the results obtained and the significance was established at p < 0.05.

Both groups were similar for baseline demographic, clinical, stone-related and anatomical characteristics. PCNL showed a much high stone free rate at 3 months than in RIRS (93.5 vs 78.8; p = 0.01). Nonetheless, the RIRS was associated with a much shorter period of operation, decreased fluoroscopy level, lesser pain rating postop, decrease in hemoglobin levels, and decreased hospitalization (all p < 0.001). The overall rates of complications were much more increased in PCNL in comparison with the control (39.1 vs 16.5; p = 0.002), such aspects as febrile episodes, urinary tract infection, blood transfusion, major complications (Clavien-Dindo grade ≥ III), and 30-day readmissions. The increased need for auxiliary procedures and re-interventions was related to RIRS.

PCNL is better used in the treatment of inferior pole renal stones not exceeding 1-2 cm in size and RIRS is better in terms of perioperative profile (lowest morbidity, faster recovery). The selection of treatment must be made on a case-by-case basis with a trade-off between the greatest clearance of the stone and the risk inherent in the treatment and characteristics of the patient.