23 © Springer Nature Singapore Pte Ltd. 2020 G. Zeng, K. Sarica (eds.), Percutaneous Nephrolithotomy, https://doi.org/10.1007/978-981-15-0575-1_3 Armamentariums Related to Percutaneous Nephrolithotripsy (PCNL) Athanasios Dellis and Athanasios Papatsoris 3.1 Nephroscopes The choice of the nephroscope is of utmost impor- tance. Although most of the scopes used are rigid ones, the nephroscope’s choice depends abso- lutely on personal preference and availability [1]. 3.1.1 Rigid Nephroscopes Rigid nephroscopes have the advantage of supe- rior optical quality due to the rod lens system, excellent irrigation and working channels. The optimal nephroscope should have a suffcient working length, a large working channel, a reduced outer diameter and a watertight entry site for instruments and accessories [1]. Practically, all nephroscope models have their optical and light cables and the irrigation lines located on the same side of the shaft. Most neph- roscope models are designed with a continuous fow system, managed with an infow and an out- fow valve. However, when using a plastic Amplatz sheath, the outer shaft with the outfow valve loses its role; in fact, the irrigation fuid can fow out between the nephroscope and the Amplatz sheath. Although rigid nephroscopes have proven their effcacy and safety through years, they are characterized by limited maneu- verability through long tracks (e.g. in cases of horseshoe kidneys) or around complex intrarenal anatomy due to the distance and the spatial loca- tion of calculi in the calyces [1, 2]. 3.1.2 Flexible Nephroscope A fexible cystoscope/nephroscope is essential during a contemporary single tract PCNL since it allows access in peripheral calyces that are not reachable with a rigid instrument (e.g. in stag- horn stones). With the fexible scope the number of tracts can be minimized. However, through the working channel only fexible instruments can be utilized. For instance, stone fragmentation can be performed only with laser lithotripsy [2]. 3.2 Renal Access Safe and accurate percutaneous renal access is of utmost importance [3]. The best approach to the kidney is ideally achieved by a transpapillary A. Dellis University Department of Surgery, Aretaieion Hospital, Athens, Greece University Department of Urology, Sismanoglio Hospital, Athens, Greece A. Papatsoris (*) University Department of Urology, Sismanoglio Hospital, Athens, Greece 3