Editorial Comment on: Randomized Controlled Trial Comparing Three Different Modalities of Lithotrites for Intracorporeal Lithotripsy in Percutaneous Nephrolithotomy by York et al. (From: York NE,Borofsky MS,Chew BH,et al. J Endourol 2017;31:1145–1151)

Acentral component of percutaneous nephrostolithotomy is an endoscopic lithotrite that safely and efficiently clears stone of all compositions from the intrarenal collecting system. The current multicenter trial studied three lithotrite combinations employing both mechanical ballistic and ultrasonic energy to fragment and evacuate with suction stone debris. What is clear from this work is that, with regard to the timely clearance of the stone burden and perioperative complications, there is minimal difference between the devices studied, nothing special and nothing new. The real question here is: are these devices sufficient, since the basic technologies employed are well more than 10 years mature?

Percutaneous nephrostolithotomy in the era of retrograde flexible ureteroscopic lithotripsy is relegated to those with the largest stone burdens, matrix stones requiring complete evacuation of this material at the time of the surgical intervention, and those who have failed ureteroscopic lithotripsy. With that in mind, the endoscopic lithotrite required for percutaneous intrarenal surgery should promptly clear the hardest stone compositions, including calcium oxalate monohydrate, brushite, and smooth cysteine. In addition, it should efficiently evacuate magnesium ammonium phosphate stones and sticky matrix that often fills the collecting system. Thus, the endoscopic lithotrite should have sufficient power to dust and fragment the hardest stones, and also have probes that can be placed through a flexible nephroscope to access peripheral caliceal calculi.

The senior author, James Lingeman, a pioneer in minimally invasive surgery, has through this work challenged industry to innovate. The studied lithotrites with almost identical outcomes define a mediocre status quo. The ultimate answer may come from a different energy source, possibly combining laser energy with suction for example. It is through carefully designed studies like this that we can quantify the limitations of current technology, inspiring the next generation of biomedical engineers to deliver significant improvements.