LAUSR

Percutaneous nephrolithotomy (PCNL) is currently the treatment of choice for large and complex renal calculi. One of the main advantages of PCNL is gaining a real stone-free status in a single session. However, there are several major complications that necessitate careful patient selection for this surgery (1). In this well written manuscript the authors deal with the true rates and importance of residual fragments following PCNL surgeries done in a high volume center. They reviewed 658 PCNL procedures from 2008-2013 that underwent a CT scan on post-operative day one. The immediate and real stone free rates were lower (55%) than previously published. Moreover, the rate of spontaneous passage of very small RFs in this study is interestingly low (23.4%).  The question is whether these are real residual fragments or just parenchymal calcifications such as Randall’s plaques or even nephrocalcinosis.  It is crucial to find a way to distinguish between these two options. Furthermore, when they compared the fat...