A randomized controlled study to analyze the safety and efficacy of percutaneous nephrolithotripsy and retrograde intrarenal surgery in the management of renal stones more than 2 cm in diameter.

Objective: The gold standard for removal of renal stones more than 2 cm in diameter is percutaneous nephrolithotripsy (PCNL). Retrograde intrarenal surgery (RIRS) has become more and more fashionable because of its high safety and repeatability, especially in smaller stones. Many retrospective studies have proved its efficacy and safety in larger calculi, however. We decided to compare prospectively both procedures in terms of safety and efficacy in renal pelvic stones more than 2 cm in diameter.

Patients And Methods: This was a randomized single tertiary care center trial with two arms (32 patients in each arm). The first group comprised patients who underwent PCNL, while in the second group, there were patients in whom RIRS with a semirigid ureteroscope was used. The primary end points were hematocrit and hemoglobin drop after surgery as equivalents of safety and stone disintegration rate in terms of efficacy. The secondary end points comprised operating room time, visual analogue scale of pain, pain treatment, and hospital stay.

Results: The mean hematocrit drop after the procedure was lower in the second group. Similarly, operating room time and hospital stay were significantly shorter after RIRS in comparison with PCNL. In the second group, patients had favorable features in terms of pain intensity and treatment after the procedure. PCNL showed higher efficacy (94%) in comparison with RIRS (75%). The power of 83% was calculated for the primary end point.

Conclusion: The efficacy of RIRS is acceptable and, emphasizing its high safety, it should be considered as a valuable alternative option for management of renal pelvic stones more than 2 cm in diameter.