Editorial Comment for Demirbas et al.

Endoscopic treatment is currently the mainstay of management for urolithiasis. The high effectiveness of percutaneous nephrolithotomy (PCNL) is well documented in the literature, as are its complications. Bleeding during PCNL is directly related to the size of the dilatation. ¹ Several minimally invasive refinements in percutaneous surgery have been made to reduce access-related complications and bleeding rates. ² This was achieved mainly by reducing tract diameter, but the advantage over standard PCNL has yet to be proven. ³

The effectiveness of retrograde intrarenal surgery (RIRS) is decreasing with increasing stone burden. However, with improvements of laser machines, it is currently much easier to ablate stones into fine powder. Currently, high-power systems enable the treatment of larger stones in a shorter time.

Nevertheless, considering safety and effectiveness, the optimal treatment option for moderate size kidney stones is still located in a gray zone.

In this randomized study, the authors compare the effectiveness of ultramini PCNL and RIRS in treating moderate size kidney stones. They found similar success and complication rates. However, in the RIRS group, the radiation doses were lower and the Visual Analog Scale (VAS) score and return to daily activities measurements were better. In the lower pole subgroup, the success rate of ultramini PCNL (UMPCNL) was much higher (93.3% vs 42.9%).

The advantages of the standard PCNL over RIRS are the ability to reach stones in almost every calix, and the ability to suction or grasp fragments out. However, when comparing UMPCNL with RIRS, the only advantage is the former and this is probably the reason for their similar stone-free rates in the whole group and better results with the lower calix stones.

The favorable results in this study along with the miniaturization of PCNL technology may provide a safe and effective alternative to standard PCNL in selected cases, and potentially support its widespread use in the future.